refund api order

Error message received when refunding an order:
“An error occurred while attempting to create the refund using the payment gateway API”

What could this be?

### WordPress Environment ###

Home URL: https://lightbox-academy.at
Site URL: https://lightbox-academy.at
WC Version: 3.5.4
Log Directory Writable: ✔
WP Version: ❌ 4.9.9 - Es ist eine neuere Version von WordPress verfügbar (5.0.3)
WP Multisite: –
WP Memory Limit: 512 MB
WP Debug Mode: –
WP Cron: ✔
Language: de_DE
External object cache: –

### Server Environment ###

Server Info: Apache
PHP Version: 7.2.14
PHP Post Max Size: 50 MB
PHP Time Limit: 900
PHP Max Input Vars: 9000
cURL Version: 7.52.1
OpenSSL/1.0.2q

SUHOSIN Installed: –
MySQL Version: 5.7.25-1
Max Upload Size: 50 MB
Default Timezone is UTC: ✔
fsockopen/cURL: ✔
SoapClient: ✔
DOMDocument: ✔
GZip: ✔
Multibyte String: ✔
Remote Post: ✔
Remote Get: ✔

### Database ###

WC Database Version: 3.5.4
WC Database Prefix: lb_
MaxMind GeoIP Database: ✔
Datenbank-Gesamtgröße: 76.33MB
Datenbank-Datengröße: 52.66MB
Datenbank-Indexgröße: 23.67MB
lb_woocommerce_sessions: Daten: 12.14MB + Index: 0.63MB
lb_woocommerce_api_keys: Daten: 0.00MB + Index: 0.01MB
lb_woocommerce_attribute_taxonomies: Daten: 0.00MB + Index: 0.01MB
lb_woocommerce_downloadable_product_permissions: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_order_items: Daten: 0.05MB + Index: 0.03MB
lb_woocommerce_order_itemmeta: Daten: 0.42MB + Index: 0.27MB
lb_woocommerce_tax_rates: Daten: 0.00MB + Index: 0.01MB
lb_woocommerce_tax_rate_locations: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_shipping_zones: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_shipping_zone_locations: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_shipping_zone_methods: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_payment_tokens: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_payment_tokenmeta: Daten: 0.00MB + Index: 0.00MB
lb_woocommerce_log: Daten: 0.00MB + Index: 0.00MB
lb_blc_filters: Daten: 0.00MB + Index: 0.00MB
lb_blc_instances: Daten: 0.05MB + Index: 0.02MB
lb_blc_links: Daten: 0.53MB + Index: 0.07MB
lb_blc_synch: Daten: 0.02MB + Index: 0.02MB
lb_commentmeta: Daten: 0.00MB + Index: 0.01MB
lb_comments: Daten: 0.22MB + Index: 0.09MB
lb_duplicator_packages: Daten: 0.00MB + Index: 0.00MB
lb_ewwwio_images: Daten: 0.09MB + Index: 0.09MB
lb_failed_jobs: Daten: 0.02MB + Index: 0.00MB
lb_links: Daten: 0.00MB + Index: 0.00MB
lb_mailchimp_carts: Daten: 0.02MB + Index: 0.00MB
lb_options: Daten: 4.35MB + Index: 0.15MB
lb_pmxe_exports: Daten: 0.16MB + Index: 0.00MB
lb_pmxe_google_cats: Daten: 0.26MB + Index: 0.05MB
lb_pmxe_posts: Daten: 0.03MB + Index: 0.01MB
lb_pmxe_templates: Daten: 0.00MB + Index: 0.00MB
lb_pmxi_files: Daten: 0.02MB + Index: 0.00MB
lb_pmxi_history: Daten: 0.02MB + Index: 0.00MB
lb_pmxi_images: Daten: 0.02MB + Index: 0.00MB
lb_pmxi_imports: Daten: 0.02MB + Index: 0.00MB
lb_pmxi_posts: Daten: 0.02MB + Index: 0.03MB
lb_pmxi_templates: Daten: 0.02MB + Index: 0.00MB
lb_postmeta: Daten: 7.58MB + Index: 4.17MB
lb_posts: Daten: 19.89MB + Index: 16.37MB
lb_queue: Daten: 0.02MB + Index: 0.00MB
lb_revslider_css: Daten: 0.09MB + Index: 0.00MB
lb_revslider_layer_animations: Daten: 0.00MB + Index: 0.00MB
lb_revslider_navigations: Daten: 0.00MB + Index: 0.00MB
lb_revslider_sliders: Daten: 0.10MB + Index: 0.00MB
lb_revslider_slides: Daten: 0.05MB + Index: 0.00MB
lb_revslider_static_slides: Daten: 0.00MB + Index: 0.00MB
lb_smush_dir_images: Daten: 0.00MB + Index: 0.00MB
lb_termmeta: Daten: 0.00MB + Index: 0.01MB
lb_terms: Daten: 0.01MB + Index: 0.02MB
lb_term_relationships: Daten: 0.01MB + Index: 0.03MB
lb_term_taxonomy: Daten: 0.01MB + Index: 0.02MB
lb_usermeta: Daten: 0.46MB + Index: 0.31MB
lb_users: Daten: 0.03MB + Index: 0.04MB
lb_vtprd_purchase_log: Daten: 0.02MB + Index: 0.02MB
lb_vtprd_purchase_log_product: Daten: 0.02MB + Index: 0.02MB
lb_vtprd_purchase_log_product_rule: Daten: 0.02MB + Index: 0.02MB
lb_wc_download_log: Daten: 0.00MB + Index: 0.00MB
lb_wc_webhooks: Daten: 0.00MB + Index: 0.00MB
lb_wfBadLeechers: Daten: 0.00MB + Index: 0.00MB
lb_wfBlockedCommentLog: Daten: 0.00MB + Index: 0.00MB
lb_wfBlockedIPLog: Daten: 0.01MB + Index: 0.01MB
lb_wfBlocks: Daten: 0.00MB + Index: 0.00MB
lb_wfBlocks7: Daten: 0.00MB + Index: 0.00MB
lb_wfBlocksAdv: Daten: 0.00MB + Index: 0.00MB
lb_wfConfig: Daten: 0.43MB + Index: 0.01MB
lb_wfCrawlers: Daten: 0.00MB + Index: 0.00MB
lb_wfFileChanges: Daten: 0.00MB + Index: 0.00MB
lb_wfFileMods: Daten: 3.19MB + Index: 0.69MB
lb_wfHits: Daten: 0.09MB + Index: 0.02MB
lb_wfHoover: Daten: 0.00MB + Index: 0.00MB
lb_wfIssues: Daten: 0.02MB + Index: 0.01MB
lb_wfKnownFileList: Daten: 1.62MB + Index: 0.21MB
lb_wfLeechers: Daten: 0.02MB + Index: 0.03MB
lb_wfLiveTrafficHuman: Daten: 0.00MB + Index: 0.01MB
lb_wfLockedOut: Daten: 0.00MB + Index: 0.00MB
lb_wfLocs: Daten: 0.00MB + Index: 0.00MB
lb_wfLogins: Daten: 0.16MB + Index: 0.03MB
lb_wfNet404s: Daten: 0.00MB + Index: 0.00MB
lb_wfNotifications: Daten: 0.04MB + Index: 0.00MB
lb_wfPendingIssues: Daten: 0.00MB + Index: 0.00MB
lb_wfReverseCache: Daten: 0.00MB + Index: 0.00MB
lb_wfScanners: Daten: 0.00MB + Index: 0.00MB
lb_wfSNIPCache: Daten: 0.00MB + Index: 0.00MB
lb_wfStatus: Daten: 0.09MB + Index: 0.04MB
lb_wfThrottleLog: Daten: 0.00MB + Index: 0.00MB
lb_wfTrafficRates: Daten: 0.00MB + Index: 0.00MB
lb_wfVulnScanners: Daten: 0.00MB + Index: 0.00MB
lb_wpmm_subscribers: Daten: 0.02MB + Index: 0.00MB
lb_yoast_seo_links: Daten: 0.15MB + Index: 0.04MB
lb_yoast_seo_meta: Daten: 0.03MB + Index: 0.04MB

### Post Type Counts ###

attachment: 167
cf7_style: 13
custom_css: 1
customer_groups: 1
customize_changeset: 8
fusion_element: 25
fusion_template: 2
invoice: 344
nav_menu_item: 68
oembed_cache: 3
page: 36
popup_theme: 6
post: 38
product: 65
product_variation: 78
pys_fb_event: 1
revision: 202
shop_coupon: 44
shop_order: 385
shop_order_refund: 23
tribe_events: 23
tribe_venue: 1
tribe_wooticket: 1
us_footer: 1
us_header: 1
us_portfolio: 18
us_testimonial: 29
us_widget_area: 5
vc_settings_preset: 3
vtprd-rule: 1
wc_voucher: 3
wc_voucher_template: 1
wpcf7_contact_form: 2

### Security ###

Secure connection (HTTPS): ❌
					Dein Shop benutzt kein HTTPS. Erfahre mehr über HTTPS und SSL-Zertifikate.
Hide errors from visitors: ✔

### Active Plugins (36) ###

B2B Market: von MarketPress – 1.0.2
Contact Form 7: von Takayuki Miyoshi – 5.1.1
GDPR Cookie Consent: von WebToffee – 1.7.3
Duplicate Post: von Enrico Battocchi – 3.2.2
Duplicator: von Snap Creek – 1.3.4
Event Tickets Plus: von Modern Tribe
Inc. – 4.9.2

Event Tickets: von Modern Tribe
Inc. – 4.9.4

The Events Calendar PRO: von Modern Tribe
Inc. – 4.5.3

Fusion Builder: von ThemeFusion – 1.8
Fusion Core: von ThemeFusion – 3.8
Google Analytics Dashboard for WP (GADWP): von ExactMetrics – 5.3.7
Hello Dolly: von Matt Mullenweg – 1.7
Loco Translate: von Tim Whitlock – 2.2.0
Mailchimp for WooCommerce: von Mailchimp – 2.1.12 – Nicht getestest mit der aktiven WooCommerce-Version
Newsletter2Go: von Newsletter2Go – 4.0.07
Popup Maker: von WP Popup Maker – 1.7.30
Really Simple SSL: von Rogier Lankhorst
Mark Wolters – 3.1.3

Recent Tweets Widget: von Noah Kagan – 1.6.8
Slider Revolution: von ThemePunch – 5.4.8
Search & Replace: von Inpsyde GmbH – 3.2.0
The Events Calendar: von Modern Tribe
Inc. – 4.7.4

TinyMCE Advanced: von Andrew Ozz – 5.0.1
The Events Calendar Extension: Advanced iCal Export: von Modern Tribe
Inc. – 1.0.0

Event Tickets Plus Extension: Enhance Woo Order Templates: von Modern Tribe
Inc. – 1.0.1 – Nicht getestest mit der aktiven WooCommerce-Version

UpdraftPlus - Backup/Restore: von UpdraftPlus.Com
DavidAnderson – 2.16.2.0

WooCommerce Billomat: von Billomat – 2.3.2 – Nicht getestest mit der aktiven WooCommerce-Version
WooCommerce PayPal Checkout Gateway: von WooCommerce – 1.6.8
WooCommerce Stripe-Gateway: von WooCommerce – 4.1.14
German Market: von MarketPress – 3.8
WooCommerce Name Your Price: von Kathy Darling – 2.9.3
WooCommerce PDF Product Vouchers: von SkyVerge – 3.5.1 – 3.5.2 ist verfügbar
WooCommerce: von Automattic – 3.5.4
WordPress Importer: von wordpressdotorg – 0.6.4
Yoast SEO: von Team Yoast – 9.5
WP All Import: von Soflyy – 3.4.9
WP Maintenance Mode: von Designmodo – 2.2.2

### Settings ###

API Enabled: ✔
Force SSL: –
Currency: EUR (€)
Currency Position: left_space
Thousand Separator: .
Decimal Separator: ,
Number of Decimals: 2
Taxonomies: Product Types: external (external)
grouped (grouped)
simple (simple)
variable (variable)

Taxonomies: Product Visibility: exclude-from-catalog (exclude-from-catalog)
exclude-from-search (exclude-from-search)
featured (featured)
outofstock (outofstock)
rated-1 (rated-1)
rated-2 (rated-2)
rated-3 (rated-3)
rated-4 (rated-4)
rated-5 (rated-5)

### WC Pages ###

Shop-Basis: ❌ Seiten-ID ist gesetzt
aber die Seite existiert nicht

Warenkorb: #1997 - /warenkorb/
Kasse: #1998 - /kasse/
Mein Konto: #1999 - /mein-konto/
Allgemeine Geschäftsbedingungen: #13 - /allgemeine_geschaeftsbedingungen/

### Theme ###

Name: Avada Child
Version: 1.0.0
Author URL: https://theme-fusion.com
Child Theme: ✔
Parent Theme Name: Avada
Parent Theme Version: 5.8
Parent Theme Author URL: http://themeforest.net/user/ThemeFusion
WooCommerce Support: ✔

### Templates ###

Overrides: Avada/woocommerce/cart/cart.php
Avada/woocommerce/checkout/form-pay.php
Avada/woocommerce/checkout/review-order.php
Avada/woocommerce/checkout/thankyou.php
Avada/woocommerce/loop/loop-start.php
Avada/woocommerce/single-product/add-to-cart/variable.php
Avada/woocommerce/single-product/short-description.php
Avada/woocommerce/single-product/tabs/additional-information.php
Avada/woocommerce/single-product/tabs/description.php

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