Yup !
It's terrible ...right

I have been spending $1.99 on glass aquarium thermometers.
I stick them everywhere. At that price they are affordable enough to put a few in each enclosure.
Just pull the suction cup off and move them around. Very accurate.

Floating Thermometer - Economy | thatpetplace.com

As for a decent hygrometer ???? I think it may be ......well ........experience
Amy - mine get stuck on 99% too.
I have to admit, I have removed mine. Such a terrible waste of $$$.