I got a few cases (intermittent) when some of the approver (I gave approver contribute permission) try to approve the task assigned (flexi task), it will get error.
I attached the print screen of error below.
Use the Correlation ID listed in the screenshot to examine the SHarePoint logs. This will give you an idea of what the source of the error is. If you're not used to examining the SharePoint logs then post all the messages relating to this ID on here and we'll try to help further.
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