Avaya 9620 User Manual page 194

Consulting the manual as required
Troubleshooting
A number cannot be set up
Ask your system administrator whether this feature has been activated for your
telephone.
A phone number dialed by code dialing cannot be extended
Possibly the "Extension" feature for the code dial destination was not enabled in the
communication server. For more information, contact your system administrator.
A call is shown in the display but your telephone does not ring
Check whether the ringing tone is deactivated (in the Do not disturb menu).
Prolonged IP address conflict
From the time it is commissioned, the IP phone checks repeatedly whether there is
another device in the network with the same IP address and is therefore interfering
with network access. If this is the case, the terminal is not functional; other devices
also experience malfunctions. This message will continue to be displayed as long
as the conflict exists.
Your system administrator must resolve the error in the network.
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