does it move into the trigger box, or does it stick OUT so the magazine cannot be inserted?
If it moves back, you have most likely lost some pieces in the trigger box. I have owned a G&G G96, and I will tell you the trigger mech does not seem to be proportionate to the quality of everything else.
Unless you are talking about the COCKING PIECE, then that is most likley your issue. If you ARE talking about the cocking piece, which is on the exterior of bolt, then this means that your trigger sear is not connecting (or holding) the piece. This can either be caused by excessive wear, or it has moved. Have you taken your gun apart about the time it happened? If thats the case then you will need to inspect your trigger box to see if pieces are missing that are causing it to move.
And also, Make An Intro Post!