You have nodes with conflicting names ERROR

I thought this was a bug that was fixed ages ago, but I've recently come across a part where nodes are apparently having conflicting names but ONLY one node exists. I have not copied and pasted nodes to cause any Node_1122 duplicates. I am at a loss, and until this is fixed, I have lost potentially hours of time

if it has errors, it would be nice to have the names highlighted in a dialog box to edit the core node name in the background or apply some sort of 'auto fix'