IHC-200 cannot setup?

Hey folks! So I have been using my Inkbird IHC-200 for a few months now with no issues, however now I cannot enter set up mode. I hold down the Set button for 3 seconds and nothing happens. Oddly enough, I can hold down the Set and Down button, and the unit turns off. Hold them again, and the unit turns on. So I am assuming something is wrong with the Up button?

Could you please loosen the screws on the back of the controller a little, then unplug the controller, press the ‘set’ button until the plug is inserted. It will enter the test mode, please press the ‘up’ or ‘down’ button. Some codes may be displayed on its screen, which is normal.
The unplug and replug the controller (you do not need to press the ‘set’ button this time), it will enter the normal mode.
Please test whether it can enter the set up mode?
If it doesn’t work, please send the screenshot/link of this post and the order information to support@inkbird.com.