We double checked it and found that this was an error in our document URL case. R20 does not support this URL. Thank you very much for your feedback, we will delete it later.
At the same time, we apologize for the trouble it has caused you.
R20 does not have an anti-tamper function. Maybe you can consider replacing it with other multi-dwelling button devices, such as X912 S532 that support anti-tamper functions.
