Hello @Helmut72,
Good question. Name and Display name are two different things. For, example:
If you have multiple accounts on a single Android client and you want to distinguish between them then you can change the "Name" field to Office 1 (ext.100), Office 2 (ext.101), Office 3 (ext.102) and so on. If the phones will re-provision then the Name will stay untouched.
The Display Name is the name of the SIP Account on PBX (Extention) and it cannot be changed because phone will re-provision on startup and it will replace the Display Name with name specified on the PBX.
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