Headband doesn't stay tight



I’ve had muse for about a week now and have been enjoying it despite a few struggles with getting it to read properly, particularly the green sensor on the front left of my forehead. I can usually get it to read fine after sitting it tightly on my head for a little while, but when I do struggle it’s always the front left green light that won’t stay on.
Today I noticed that the left side of the band that can extend and be made smaller is looser than the right side and sometimes slightly loosens if I move my jaw while wearing it. I was wondering if this could be anything to do with the bad reading sensor?
Maybe the band on the left can’t stay tight enough because it loosens?

Anyone else have a similar problem?