Problem with loose electrical connection


For some reason in few days after installation the lamp stopped working.

I noticed if I push on the bottom of the lamp towards the ceiling it starts working, but when I don’t push it stops working again.

First I though the problem was with loose wire connection, but after checking it it looks OK.

Is it possible that the electrical connection is getting lost in the circular connector?

Maybe I can put some insulators inside the rings to get the connection?

Thanks in advance!