| Mine did this, too. It's probably because it's a little too tight, and that's stretching the zippered area too taut. ( I found that mine had actually stretched out a line of stitching which sewed he flap down to the zipper in the chest area. If that's the case, reinforce the stitching. )
You could try laying the lame flat, folding the flap where you want it, and putting something heavy, like books, on it, to "train" it into a better attitude... |