An infinite import loop has been detected. The following Assets were imported multiple times, but no changes to them have been detected. Please check if any custom code is trying to import them:

I have a pretty big unity project with a lot of 3D models and upgrading the unity version is always a big problem. I recently upgraded this project from version 2019.3.2f1 to 2020.3.6f1 and everything was working fine but I wanted to use the Play Asset Delivery, so upgraded it once again to 2020.3.28f1 and I get this error. I think it could be because of low disk space, my SSD was almost full while importing but I'm not entirely sure. I am reverting back to 2020.3.6f1 and will free some space and upgrade it once again.

Can anyone please help.

 An infinite import loop has been detected. The following Assets were imported multiple times, but no changes to them have been detected. Please check if any custom code is trying to import them:
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