Laptop not booting after DC socket connector replacement

Hi everyone,

my laptop had some problems with the DC socket connector.

Sometimes it shut off if I moved the power cable. The DC was replaced before and I think they have put a bad DC socket connector as it was really loose when connecting the cable.

As this follows I have replaced it again with the original DC socket connector and now the computer boots and shuts off after a few seconds.

I have also changed the heat paste but nothing changed.

Can anyone help?

Thanks.