So I installed V12 and imported one of my custom itemtypes (Versionable) from V11 into it. (including all methods, forms, etc) Everything is working fine except one or two records. When I modify and save the record I get (An item with the same key has already been added.) error. I turned on the debugger and the error occurs when the itemtype is trying to generate a new ID.I tried deleting all server methods, workflow, lifecycle, etc. Still no luck
Any help would be appreciated.