Boot not closing on 147

Hi,

The boot on my Alfa 147 has suddenly stopped locking when I close it. It's
been used several times today with no trouble but then on my last attempt to
close it, it wouldn't lock closed. I've tried several times and also
sprayed the lock with WD40, which didn't make any difference.

Has anyone else had this problem and can suggest a solution, or is it a
matter of waiting until Monday and taking it to an Alfa garage?

Thanks,
Tom