Instep gaps??

Every sock I knot seems to have gaps when I pick up the instep stitches on the left side of the sock. I am even adding an extra stitch on each side of the instep stitches when I pick them up to try and reduce gaps, but for some reason the left sides keep getting this?? It somehow seems to be even before the instep stitches, maybe the stitch there is just getting really stretched while I’m working on the heel flap? Just puzzled since it’s only the one side having problems. Tips on preventing this and fixing it at this point are appreciated!