Post notifications not working

Hello,
since a few weeks Mailpoet obviously stopped working at the a. m. installation. See screenshot post-notifications (https://www.wuo-marketing.de/wp-content/uploads/2023/03/post-notifications.png) which shows that there have not been sent any post notifications although in the field “select a frequency” there is still “immediately (after publishing a post)” activated. In the meantime several post have been published!
To exclude server side errors we moved from Ionos server to Mailpoet sending service. All relevant hooks are in green (see screenshots send-with (https://www.wuo-marketing.de/wp-content/uploads/2023/03/send-with.png) and key-activation (https://www.wuo-marketing.de/wp-content/uploads/2023/03/key-activation.png)), but we still can not see that it works.

Furthermore, you can read here the recent site health report which may help you to find errors

Your assistance would be very much appreciated.

Thanks & best regards.
Thomas

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