Content Views stops working regulary

dear supoort Team,

Today Content Views plugin stops working on my webiste https://citba-dev.mwolowski.com from time to time and then works again…

When it breaks there is no gallery visible but only the shortcut [post_gallery] like here https://citba-dev.mwolowski.com/installations/
Then suddenly I was able to use it again and it worked normally to stop after an hour and disappeared from all the posts where it was used.

error details screenshot here:https://citba-dev.mwolowski.com/error-details/

Thank you in advance,
Ewa

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