I removed the whole seat and took it for the re-test and the guy goes cheeky but because its not in there its a pass. so job done still need to get it sorted but at least i got more time to play with now.

Thanks for alll the advice guys i've tried everything cant get it done so going to just take it to a spares place in Nottingham guys been really helpful over the fone and said will sort it out if i bring it down to him, nothing to loose guys soo confident he can do it its unreal.
 
I thought i was having the exact same problem with mine when it went in for the MOT, but one of the mechanics told me it passed anyway. Apparently if the seat doesn't fully clip back down after you've had them forward the middle belt wont release properly. Just make sure i give it a bit of a bang now every time i put it back so it does go into place and the belt will release without catching
 
all i did with mine was take out the bolt in the middle under the cushion let the seat belt retract alittle then the locking mech will release and it will work i had to do it every few weeks on my toledo