The approval section of the workflow was working perfectly until:
1. I added approval required in Versioning Settings of the Workflows Task list and then removed the setting.
2. Deleted a Status choice column.
3. All permission groups were working previously.
I am not getting the error that Something has gone wrong when trying to approve any task.
I am assuming I need to reset the Workflows Task List to the default one without deleting the customised Nintex Form that I have created.
You help would be greatly appreciated.