Flat rate shipping displayed for some postcodes and not others

Hello,

At checkout, when the customer enters their address and postcode, it only displays the free shipping and local shipping options for some postcodes and the correct flat rate for others.
Even if the postcode is included in the flat rate shipping with a wildcard it still doesn’t display it. What could be the problem?

System Status Report

### WordPress Environment ###

WordPress address (URL): [Redacted]
Site address (URL): [Redacted]
WC Version: 9.4.3
Legacy REST API Package Version: The Legacy REST API plugin is not installed on this site.
Action Scheduler Version: ✔ 3.8.2
Log Directory Writable: ✔
WP Version: 6.7.1
WP Multisite: –
WP Memory Limit: 256 MB
WP Debug Mode: –
WP Cron: ✔
Language: en_US
External object cache: –

### Server Environment ###

Server Info: Apache
PHP Version: 8.0.30
PHP Post Max Size: 128 MB
PHP Time Limit: 30
PHP Max Input Vars: 1000
cURL Version: 8.9.1
OpenSSL/1.1.1w

SUHOSIN Installed: –
MySQL Version: 5.7.44-log-cll-lve
Max Upload Size: 128 MB
Default Timezone is UTC: ✔
fsockopen/cURL: ✔
SoapClient: ✔
DOMDocument: ✔
GZip: ✔
Multibyte String: ✔
Remote Post: ✔
Remote Get: ✔

### Database ###

[REDACTED]

### Post Type Counts ###

attachment: 201
custom_css: 2
customize_changeset: 5
elementor_library: 3
elementor-hf: 1
nav_menu_item: 24
page: 12
post: 1
product: 27
product_variation: 86
revision: 478
shop_order_placehold: 2
wp_global_styles: 2
wp_navigation: 1
wpforms: 2

### Security ###

Secure connection (HTTPS): ✔
Hide errors from visitors: ✔

### Active Plugins (9) ###

Starter Templates: by Brainstorm Force – 4.4.8
Duplicate Page: by mndpsingh287 – 4.5.4
Duplicator: by Duplicator – 1.5.11.2
Elementor: by Elementor.com – 3.25.10
Elementor Header & Footer Builder: by Brainstorm Force
Nikhil Chavan – 1.6.47

Simple 301 Redirects: by WPDeveloper – 2.0.11
WooCommerce: by Automattic – 9.4.3
Yoast SEO: by Team Yoast – 23.9
WPForms Lite: by WPForms – 1.9.2.2

### Inactive Plugins (4) ###

Custom Product Tabs for WooCommerce: by Code Parrots – 1.8.5
UpsellWP Lite - WooCommerce Upsell, Cross-sell and Order Bumps: by UpsellWP – 2.1.4
Variation Swatches for WooCommerce: by CartFlows – 1.0.12
Worldpay eCommerce for WooCommerce: by Worldpay – 1.0.4

### Settings ###

Legacy API Enabled: –
Force SSL: –
Currency: GBP (£)
Currency Position: left
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)

Connected to WooCommerce.com: –
Enforce Approved Product Download Directories: ✔
HPOS feature enabled: ✔
Order datastore: Automattic\WooCommerce\Internal\DataStores\Orders\OrdersTableDataStore
HPOS data sync enabled: –

### Logging ###

Enabled: ✔
Handler: Automattic\WooCommerce\Internal\Admin\Logging\LogHandlerFileV2
Retention period: 30 days
Level threshold: –
Log directory size: 6 KB

### WC Pages ###

Shop base: #996 - /shop/
Cart: #997 - /cart/ -  Contains the [woocommerce_cart] shortcode
Checkout: #998 - /checkout/ -  Contains the [woocommerce_checkout] shortcode
My account: #999 - /my-account/
Terms and conditions: ❌ Page not set

### Theme ###

Name: Maden Eco Child
Version: 1.0.0
Author URL: https://infoserve.com
Child Theme: ✔
Parent Theme Name: Astra
Parent Theme Version: 4.8.7
Parent Theme Author URL: https://wpastra.com/about/?utm_source=theme_preview&utm_medium=author_link&utm_campaign=astra_theme
WooCommerce Support: ✔

### Templates ###

Overrides: –

### Admin ###

Enabled Features: activity-panels
analytics
product-block-editor
coupons
core-profiler
customize-store
customer-effort-score-tracks
import-products-task
experimental-fashion-sample-products
shipping-smart-defaults
shipping-setting-tour
homescreen
marketing
mobile-app-banner
navigation
onboarding
onboarding-tasks
pattern-toolkit-full-composability
product-custom-fields
remote-inbox-notifications
remote-free-extensions
payment-gateway-suggestions
printful
shipping-label-banner
subscriptions
store-alerts
transient-notices
woo-mobile-welcome
wc-pay-promotion
wc-pay-welcome-page
launch-your-store

Disabled Features: product-data-views
experimental-blocks
minified-js
product-pre-publish-modal
settings
async-product-editor-category-field
product-editor-template-system
blueprint
reactify-classic-payments-settings
use-wp-horizon

Daily Cron: ✔ Next scheduled: 2024-12-05 08:42:58 +00:00
Options: ✔
Notes: 74
Onboarding: skipped

### Action Scheduler ###

Complete: 110
Oldest: 2024-11-03 19:54:43 +0000
Newest: 2024-12-04 13:24:16 +0000

Failed: 4
Oldest: 2024-08-13 08:44:21 +0000
Newest: 2024-12-04 11:17:46 +0000

Pending: 7
Oldest: 2024-12-04 22:54:30 +0000
Newest: 2024-12-08 15:53:19 +0000


### Status report information ###

Generated at: 2024-12-04 13:25:18 +00:00

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