Thank you for contacting us.
Sorry to hear about the bug when trying to delete a user and our team will do everything we can to help you get it working.
The error message you provided is generally returned by WordPress installations when there is something wrong with the PHP configuration on your web server.
I recommend reviewing your servers settings to make sure they meet the recommended configurations contained in this guide from our support center (https://www.boldgrid.com/support/troubleshooting/how-to-change-php-settings/).
Hopefully that helps you get this problem fixed, but please let us know if there is anything else that we can do to assist you.
This error is still occuring in February 2022 and has nothing to do with PHP settings, I think it has to do with nonc conflict with the plugin banner. Click to close the banner permanently and this should be fixed.
Thank you for posting the workaround Petrus!
We are currently tracking this issue in our Total Upkeep repository and hopefully we should be able to get a fix released in an upcoming update for Total Upkeep.
Subscribing to that GitHub issue thread will allow you to get updates on the progress of our fix as soon as they occur.
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