Hi, in another post, @CHMultimedia told us than Android 10 have a lot of bugs ans insist to the fact another update will be done, maybe this is what's making your problem...
Personnaly, if it was my device, only thing i'd try would be a wipe cache partition, you can download this file for wiping all Samsung devices
Does your card works on PC ?
Use a storage testing software like H2testw, available on PCs.
Also, you should read this article :