volte problem in airtel

[fakevikas1]

so i just got a new airtel sim . After activation their was no option of volte for the sim and volte wasnt showing in notification tray. After some days i used this airtel sim in another zenfone max pro and it was showing volte and then i swapped another airtel sim into my phone and volte was working.
But then i inserted my airtel sim again and volte option wasnt present in settings option neither it was showing volte.
so whenever i make calls the sim gets to 2g network
please help
Please tell us some basic information before asking for help:

Model Name:zenfone max pro m1
Firmware Version: latest
Rooted or not:no
Frequency of Occurrence:
APP Name & APP Version (If your issue relates to the app):
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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[Yachendra]

It's probably the issue with SIM, check with your network provider. Also, check whether your device is updated with latest firmware version.

[fakevikas1]

but when i put the sim in another phone its working volte

[kundansingh9307]

Reset your phone and problem will be solved. I have already faced this issue with Airtel 4g sim.

[victor010]

Hi, we'd request you follow the below steps:
1. Check your phone for latest software version.
2. Clear system cache.
3. Try the same under safe mode:
Hold the power button for 5 seconds => When the screen flashes with option => Press & hold power option => You will get an option to restart in safe mode
4. If still you face the issue factory reset your phone after taking a full backup:  https://www.asus.com/support/FAQ/1006346/