SD Card not reading; causes shut down

[J.Sims]

Hi, I'm having a problem where my SD card suddenly doesn't work with UAPP.  It works fine in other apps etc.  Other SD cards are also working fine with UAPP.  I'm using a Galaxy S7.  The SD card I'm trying to use is my main 128GB.  When I try to have UAPP scan the card for music files it starts off but then completely closes the app without loading the files, rendering the SD card unusable with UAPP.  What's the solution?

Regards,
Jerome