Wrong.
So where is it?
A schematic is the only way to communicate unambiguously what wiring you have.
You repeated this
given your description means you have not connected the grounds together. In this context ground is not the mains ground, it is the negative of both power supplies use should be connected together. You have to do this in your wiring, we need to see which is wrong, your words or your wiring.
You haven’t even looked at the link I posted.