I need some help with a small issue with my sweater necklines. When I get to the pattern part where I bind off for the neckline, where I join the second ball so that I can knit both sides at the same time to make the shoulders, I seem to always have a hole/gap between the stitch where ball 1 is and the stitch where I have joined the second ball for the other shoulder. I always have to try and go back and somehow repair it, which I do, but I would like to know what it is that I could possibly be doing wrong so I can change it and wouldn't have this problem. Thanks! I am only about 8 rows from having to start the neckline and shoulder decreases on the current sweater I am knitting.