Help please . external drive shows up but no files accessible in bridge

I am using SOX 10.15 Catilina and Bridge 2019 CC. I have had no issues until the weekend. When I plugged in my external drive Bridge asked if I wanted to allow it to access the external drive. I accidently pressed no and now I canot access any external drives. I am a teacher and the numerous drives I have contain all my schools yearbook images... any help would be much appreciated... Thanks