Galaxy SM-T520 stopped seeing microsd card slot - not memory card issue

[killerkayak]

My Galaxy SM-T520 Galaxy Tab Pro 10 just stopped seeing the microSD card I had installed in it. The same card was in it for the past year, worked swift. Took the card out, works great in my PC and ASUS tablet I have. Tried 3 other cards that work in devices, the tablet doesn't see the microSD slot. Won't let me "mount SD Card". Installed SD Insight, doesn't see that there is a microSD card at all. Any ideas? My tablet that had lots of memory is now limited to the installed 16 GB.