I can't register an M25 on an M700.
I launch the registration procedure which ends by returning to the initial status (deregistered) after entering the pin and waiting for registration.
There are no errors in the log.
M25 fw 03.55 Branch: 0025
M700 fw 04.10/B0004
We will need to have a look at your debug logs. I replied to you in ticket #29979