sun roof failing to shut

[freedriver]

Hi all , The sunroof on my 04xt isn't closing properly on the passanger side . It all works fine untill the last 20mm or so.

I have taken the glass out and had a look and the frame on the passenger side is not moving forward or up as much as the drivers side by about 20-30mm.I managed to get it shut by pushing the frame forward but if i open it again it will not shut all the way again.

It seems to have a bit of slack in the mech. Can any one shed some light as how i might be able to fix this? Cheers