Hello,
Have you tried to unplug the phone Micro SD card and connected it to your PC?
How does this Samsung phone memory card show on your PC?
Honestly, no matter whether it is inaccessible or unreadable there, you can go try Samsung phone data recovery freeware to [https://www.icare-recovery.com/howto/corrupted-memory-card-stick.html|retrieve data from corrupted Samsung Galaxy phone memory card].
Of course, if this phone memory card stops working completely and could not be detected by any device, it must fail somehow and go take it to local data recovery companies for helps.