A quick way of checking if the phone is still registered to the SIP Provider is looking at the Line Icon:
More detailed Information can be obtained via:
Press the Menu Key => select Status => select Lines
this menu will offer you now either the Line Information or the Server Status
Both of the above should provide you with a countdown Information showing the registration/subscription to the SIP Server.
If above shows nothing or no registration Information the Phone has lost it's connectivity to the SIP Server. Please use this post => here <= to attempt and troubleshoot this.
If official support is required please check how to phone or open a case here
----------------The Poly Phone UI can be used to determine the provider if this is unknown to the user of the phone.
Navigate via the Phone UI to Settings > Status > Lines may display who the provider is:
Using the Multiple Key Combination => here <= of 1, 4 and 7 shows the provisioning Server:
In the above examples, the phone is registered to the Microsoft SIP Gateway so any issues should be reported to our Partner Microsoft
If official support is required please check how to phone or open a case here
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