1TB MyPassport, can't use multiple at once

I’m trying to figure out if there’s a way around not being able to use multiple Passports at once. Unfortunately it will see that the 2nd is plugged in, through the software, but won’t recognize anything regarding it (ie name, size, what is on the hd)

You may have to go into disk management and assign it a drive letter the ngo down where it shows the drived as bars and on left is a box with names Disk1 right click on it and put online.

Joe