Hello, I bought a used BeoLine 2 telephone base, but cannot register my handsets to it, even though I  (believe I) have its PIN code. I think the maximum number of handsets was connected and the base was not reset, so I cannot register one of my own handsets. When trying to register using a BC6000mkI, I am asked to input the PIN code, after it responds with '***FAULT***'. When  using a BC6000mkII, the base just responds with 'Registration failed'. The seller has no clue unfortunately. The handsets that were connected originally were sold already. Is there a way to (hard) reset the BeoLine 2 without a connected handset? Hope someone knows! Thanks, Johan