Please tell us some basic information before asking for help:
Model Name: ZenFone Max Pro (M2)
Firmware Version: 094
Rooted or not: not
Frequency of Occurrence: always
APP Name & APP Version (If your issue relates to the app): VoLTE
In addition to information above, please also provide as much details as you can, e.g., using scenario, what troubleshooting you've already done, screenshot, etc.
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Italian carrier Ho., virtual operator of Vodafone, sterted claiming it is supporting VoLTE. On my device it doesn't work. How can I activate/use VoLTE phone calls?
I have no option while VoLTE on second Tim sim is on.