Canon AE-1 light meter needle wont move?

okay,so i had two canon ae-1's and i decided to switch the doors because one of them had a light leak,i also switched the battery too because the light meter needle wouldent move.when i changed the battery,the needle moved fine.a little while later,i put some 400 asa blk&wht film in the camera and now the needle just stays at the top of the meter.i changed the asa on the camera to 400 and have switched around the shutter speed but nothings working. what can i do to get the meter to move again? i needa get outside before it gets dark to shoot pictures of this ice formation ASAP