Since firmware version 8.9.3.51, we inhibit (by default) the option to insert letters in the dial screen.
In order to restore this possibility you can turn off the setting block_url_dialing
You can perform this in three ways:
- Through the Web User Interface (Advanced - Behavior (Tab) - Phone Behavior (Section): Block URL Dialing)
- Via HTTP Request
- Via provisioning
Once you have turned Block url dialing to off, you can enter letters again in the dial screen:
You have to change the input keyboard from "123" to "abc", by pressing the first contextual key button: