Multiple failures in Sync

Hi,

I always have the same problems with sync. Some products are shown as

• Not synced
  Not syncable Undefined status code, check WC logs

• Not synced
  Syncable

I have deinstalled all other plugins and have used a standard theme in a staging environment – there are the same failures at exactly the same products like in the live-environment.

I have set the debugging mode, so there were some further messages:

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in /xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "width" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114

Warning: Undefined array key "height" in xyz/wp-content/plugins/zettle-pos-integration/modules/zettle-php-sdk/src/Validator/WordPressImageValidator.php on line 114
274 out of 392 WooCommerce + 411 PayPal Zettle products found

Notice: Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the zettle-pos-integration domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the init action or later. Please see Debugging in WordPress for more information. (This message was added in version 6.7.0.) in xyz/wp-includes/functions.php on line 6114

Warning: Cannot modify header information - headers already sent by (output started at xyz/wp-includes/functions.php:6114) in xyz/wp-admin/includes/misc.php on line 1438

Warning: Cannot modify header information - headers already sent by (output started at xyz/wp-includes/functions.php:6114) in xyz/wp-includes/functions.php on line 7137

Warning: Cannot modify header information - headers already sent by (output started at xyz/wp-includes/functions.php:6114) in xyz/wp-admin/admin-header.php on line 9

And last, but not least, after installation and sync this message is coming:

Registration of PayPal Zettle webhooks has failed, product stock changes from PayPal Zettle will not apply. Please check WC logs and reach out the support. You can repeat webhooks registration by deactivating and activating the plugin in the plugins list.

Is there a idea, what is wrong?