Snom m9 DECT Administrator's Manual page 21

Multiple SIP Accounts with a Single Handset
1. Use Identity 1-9 for configuring all available SIP accounts one by one on the base station as shown
below:
2. Click the Handsets tab of each Identity and assign the registered handset to the Identity.
Each Identity should have the same Handset IPUI assigned to it.
Example Setups
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