Sad card reader not working

Card is in place, dongle thing is connected I pad is on but ….nothing !

i have checked via settings <general - about- and it’s showing the sd card reader wing but nothing happens?

when I go to photos it’s not showing devices at least not today but it did show devices yesterday?

Yesterday it it just said no ‘photos to show’ ? Today it doesn’t even show devices. I’m on iOS 15.4.1.

I have an old lap top that I tried it on and it worked ok got to view the video from my dash cam but now it just won’t do anything, anyone got any suggestions?