Hi,
As you changed SDcard it is assigned new ID an dAA were paired with tracks to old SDCard so new one needs to have new lookup.

Need help. I've been using MMA on my Samsung S9 for some time now and never had a problem with getting album art. I recently got a new bigger microSD card so transfered all my music over to my the card. Majority of album art is showing automatically but some is not. I have always used automatag app for any missing album art but now it is not showing on the album but only on the track. Any ideas???