Recently bought a switch 2nd hand along with a dock and AC adapter. Not displayinv on screen. Help!

Using Switch i bought at a Pawnshop with a random dock from another switch.

The console itself charges and plays fine, but it won't play on the Dock, it will charge on the Dock, but it keeps asking for the Nintendo AC Adapter that came with the switch.

I've tried hard resetting the switch, different TVs, and checked HDMI cord was working fine.

My only thoughts are that maybe the AC Adapter isn't givinv enough power, or that the Dock itself is the problem.