ID3 Tags (metadata) bug on old imported Library: edit freezes, and then it goes back

Hello!

I'm sorry if this already got asked but couldn't find anything that match my current issue.

I recently got a M2 macbook and imported my previous Itunes library.

Since I wanted to make a clean install of this mac from scratch, I didn't use my time-machine save but imported it from the base directory of files created by Itunes, sorted by Artists.

It took some time and it seems that I lost a few songs but it doesn't really matter, my real problem is the following:

• when editing ID3 tags, such as the Genre one, Itunes freezes for a few seconds.
• If the track is currently playing my changes won't apply.
• If the track wasn't playing and my changes applied, when I play it it, it freezes again then reverts to the old tags
• When editing the same tags on a newly imported song, it doesn't freeze, no matter if it is playing or not, so it seems related to my old library.

I have around 4k songs in my library, don't know if that could help.