Dash Cam 12 v feed problem

[RonnieM]

Hi,
I went to fit a dash cam to our 2017 Berlingo van and when I used a piggy back fuse link (the one that fits in place of the fuse) it has a strange effect on the circuit, basically it seems to turn the circuit permanently live i.e. the electric windows work without the ignition or the 12 v socket works without the ignition etc depending on the fuse used.

Thanks, 
Ronnie.