Weird reaction?

So I’ve been wearing my Venu3s for a couple months now and I’ve been noticing this weird reaction to the band I’m assuming? See pics. Has anybody had this same issue or know how to get rid it of it? The marks don’t hurt at all and aren’t sensitive. For reference I had an Apple Watch before I made the switch and never had any issues, even when it would get wet. I don’t normally wear my garmin in the shower