Humidity Switch vs. Hygrometer

I have a problem with my hygrometer and my humidity switch (I have a fogger attached to the humidity switch). The humidity switch (https://www.amazon.de/Lucky-Reptile-...midity+control) and the hygrometer (https://www.amazon.de/Lucky-Reptile-...ile+hygrometer) can't seem to agree with each other. It started with a 5% difference which was fine but yesterday I came home and took a look at the humidity. The hygrometer said the humidity was at 47% and the humidity switch was at 69%. This is getting absolutely ridiculous. They're beside each other (in the enclosure), how can there be a difference of 22%? Does anyone have an idea what I should do or does anyone have experience with either one of the gadgets?
Any help is appreciated.