T48S (SfB) looses Skype login information after reboot

[thomas.hauff]

Hi,

we have the YDMP version 3.1.0.13 in place and use T48S (Skype for Business edition) phones with firmware 66.9.0.73.

As soon as a T48S (SfB) phone is connected to YDMP, after the phone is rebooted, it looses the Skype login credentials.
When the phone is not connected to YDMP, it does not loose the Skype login data.
We can successfully logon to Skype for Business on the phone with the following format:

login address: SIP address
register name: <Domain>\<User logonname> or <User logonname>@<Domain>
Password: AD password

But as soon as the phone is rebooted, the credentials are gone and if we go to the login screen of Skype for Business on the phone, it automatically inserts the following:

login address: SIP address
register name: SIP address
Password: empty/deleted

Has anybody seen this?