Sandisk Micro Extreme Pro 64 gig

Card was being used in a DJI Phantom 4 Pro and is regestering in the drone but cannot be seen anywhere on the computer when plugging it in via a card reader. 

a 32 gig version can be read. 

Anyt ideas on how ot get it back 

Make sure the card reader you’re using is SDXC-compatible. Not all are.

also what OS are you using? the OS will need to support the exFAT file system as well.