Accidentally denied Photoshop 2020 permissions to read external drive on macOS Catalina

The other day I wanted Photoshop to open a file I had on an external drive. It brought up a dialog asking for permisson to access the drive but in my hurried clicking I hit DENY instead of ALLOW and now PS won't read the drive at all. If I select it in the file open window it just shows the drive's icon and there seems to be no way to undo this and re-allow access. I'm on a MacBook Pro running Catalina 10.15.6. I havent used PS in a while, and I never noticed this permission dialog to apprear before when reading my external drive. PS will not access ANY of my external drives now, not just the one I had selected when I hit deny. Restarting PS, unmounting/remounting the drive, even restarted the computer - nothing helps.

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