Time Machine not working after reboot?

Hello,

I am having an issue with Time Machine on my computer. I am using an external drive for a backup. I had the drive recognized and spent about 3 days with it doing the backup successfully. I then restarted my computer.... Now the drive won't show up. Nothing has changed other than a restart. The drive shows up on every other computer I plugged it into. It doesn't seem to ask for a drive password when I plug it in to other computers. I am not sure what it could be since it was working fine before the reboot (and other reboots do not fix it).

Mobo: gigabyte z390 designare Processor: i7-9700k Graphics: Radeon RX 580 OS: Catalina Using Open Core