Airtel — volte is not enabled on my airtel number

Address:

Ameerpet, Hyderabad, Telangana, 500073

I am unable to use volte volte services on my Airtel number even though I am using latest 4G SIM.
I went to Airtel store and he replaced me with new Airtel SIM but of now use.
Finally the store keeper said that volte is not possible to my Airtel number it is only for selected numbers and volte is possible not for all.
I called customer care many times but of no use.
No one are able to solve my problem both customer care and Airtel store keeper.
My Airtel number [protected]

Conclusion: Finally I decided to leave Airtel and go for Jio Network via MNP