Critical error when editing field mapping on woo product feed pro

Good afternoon,
I have an issue with the Feed Pro plugin and I hope you can help. I have a few feeds generated which seem to work ok for generation, but when I try to edit the filters or field mapping on any of the feeds I get this error:

“There has been a critical error on this website. Please check your site admin email inbox for instructions.
Learn more about troubleshooting WordPress.”

Unfortunately nothing comes through to the email address.
I can set edit the category mapping, but it is just the filter and field mapping pages that have this error.
I have tried an uninstall/delete and reinstall. I have checked the site status report and all seems ok.

Could you please advise?
Thanks

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