Can’t set featured product image

Hi!
I’m working on a site and i have installed your plug in.
The problem i have to deal with is that when i’m trying to add a new product,i can’t set the featured image. If i deactivate the plug in, everything works like a charm!
Can you please give me a solution to fix this problem?
Thanks in advance!

My system status :
‘
Array
(
[home_url] => https://audiomarket.gr
[site_url] => https://audiomarket.gr
[version] => 3.2.5
[wp_version] => 4.9.1
[wp_multisite] =>
[wp_memory_limit] => 40M
[wp_debug_mode] =>
[wp_cron] => 1
[language] => el
[server_info] => Apache
[php_version] => 7.0.26
[php_post_max_size] => 8M
[php_max_execution_time] => 300
[php_max_input_vars] => 10000
[max_upload_size] => 8388608
[default_timezone] => UTC
[theme] => Array
(
[name] => Flatsome Child
[version] => 3.0
[parent_theme] => Flatsome
)

[active_plugins] => Array
(
[0] => vaultpress/vaultpress.php
[1] => addendio-plus/addendio-plus.php
[2] => akismet/akismet.php
[3] => contact-form-7/wp-contact-form-7.php
[4] => google-analytics-for-wordpress/googleanalytics.php
[5] => gourl-bitcoin-payment-gateway-paid-downloads-membership/gourl_wordpress.php
[6] => gourl-woocommerce-bitcoin-altcoin-payment-gateway-addon/gourl-woocommerce.php
[7] => jetpack/jetpack.php
[8] => mailchimp-for-woocommerce/mailchimp-woocommerce.php
[9] => mailchimp-for-wp/mailchimp-for-wp.php
[10] => mypos-virtual-for-woocommerce/woocommerce-mypos-virtual.php
[11] => nextend-facebook-connect/nextend-facebook-connect.php
[12] => nextend-google-connect/nextend-google-connect.php
[13] => perfect-woocommerce-brands/main.php
[14] => regenerate-thumbnails/regenerate-thumbnails.php
[15] => timologia-for-woocommerce/wc-timologia.php
[16] => w3-total-cache/w3-total-cache.php
[17] => woo-custom-stock-status/woo-custom-stock-status.php
[18] => woo-payment-gateway-for-vivapayments/viva-woocommerce-payment-gateway.php
[19] => woocommerce-products-filter/index.php
[20] => woocommerce-products-per-page/woocommerce-products-per-page.php
[21] => woocommerce-products-visibility/woocommerce-products-visibility.php
[22] => woocommerce-services/woocommerce-services.php
[23] => woocommerce/woocommerce.php
[24] => woosidebars/woosidebars.php
[25] => wp-all-import-pro/wp-all-import-pro.php
[26] => wp-optimize/wp-optimize.php
[27] => wpai-woocommerce-add-on/wpai-woocommerce-add-on.php
[28] => yith-woocommerce-wishlist/init.php
)

[pwb_options] => Array
(
[version] => 1.6.0
[wc_pwb_admin_tab_brand_single_position] => after_meta
[old_wc_pwb_admin_tab_slug] => brand
[wc_pwb_notice_plugin_review] =>
[wc_pwb_admin_tab_slug] =>
[wc_pwb_admin_tab_brand_desc] =>
[wc_pwb_admin_tab_brand_single_product_tab] =>
[wc_pwb_admin_tab_brands_in_loop] =>
[wc_pwb_admin_tab_brands_in_single] =>
[wc_pwb_admin_tab_brand_logo_size] =>
)

)
‘

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