Medisign Orthomed Heating Pad (OM15-007)

I've used this before bought from local market, and now purchased this one from this website. Everything is fine except when I change its temperature from step 1 to step 2 and afterwards cycle it back to step 1(going to step3 and then step4 and then off and then step1). The heat it gives is too harsh and it feels like its still stuck on step4, so have to turn it off for a bit as its feels that it will give burns to the skin, after a min or 2 can turn it on back to step1 and its good
I have used it on bed while laying down as well as on chair to help my lower back. This heating pad is good other then the issue mentioned above, would still recommend it.