"Recursive" or "Recursive allowed" issue when actually BOM not recursive !!

Dear Experts,

Greetings !!

Issue:

Our client has some BOMs for which "Recursive" or "Recursivness allowed" is checked for some components. But when we drilled down the BOM manually (including Alt BOMs) till last level, we didn't see any materials got repeated or used again.

But still when we tried to uncheck and save, it says "BOM is recursive". But when we delete (not deletion flag) the whole BOM and recreate again the check is gone. And now BOM explodes in CS11/CS12.

My queries:

1. Why it is not allowing to uncheck the check box directly, but then disappears after BOM deletion and recreation??

2. And in some worst cases, it is not getting unchecked even after complete BOM deletion, when actually it's not a recursive BOM at all.

We're really confused, request experts to kindly help on the same !!

Thanks in advance !!

Jeffrey