Bales keep breaking right behind the knot

I've got a JD 336 square baler that was working fine but now the twine keeps breaking lose right behind the knot. Ties it perfectly it just seems that there's so much pressure now for some reason that it causes the twine to pull a part. It all started after the nut that holds the right side tucker finger on vibrated off which I fixed immediately. I've put a thousand bales through it this year without a problem so now I'm hoping some of you veterans could point me in the right direction

Bales keep breaking right behind the knot