Not able to delete entries or assign/reassign plugins

Hi
Love the plugin, but at some point over the last few days some of the features have stopped working.

I can’t delete entries from multiple modules,and I can’t assign or reassign a plugin anywhere.
The odd thing is, whatever I do shows up in the log though.

Normally, with a problem like this, I’d just delete a plugin and reinstall it, but I’ve spent hours tidying everything up and I only want to do that as a last resort, if absolutely necessary!
Is it possible to save a backup file?

Jasper

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