HI. I have a very strange problem.

I can't factory reset a Snom D713 phone. If I carry out the RESET procedure after **## the phone does not take the admin password: 0000.

I tried to download the snomD713-10.1.169.13-SIP-r.bin firmware, and upload it to the phone via TFTP and HTTP but even after this procedure....the phone continues to do "what it wants" as soon as it goes online and it fails to access the administration.

Is it possible that not even a firmware change can resolve this situation?

Is there another way to access the administration? otherwise I will have to return it.
Thank you all