Airtel — charged for value added services I didn't want

Thanks for using valuepack. You have been charged rs 20.0 from your airtel mobile account. For more services, call 56789
The above message came in pre paid airtel number [protected]
I have not requested any vas. I called 155223 for deactivation.
I want refund of rs.20 back
I use a minimum stv pack 199 after paying months for no net connection and lost 10 gb data when i converted to pre paid connection from post paid. I keep bare minimum of rs.100 in talk time for emergency.
I have no intention o[censored]sing any unnecessary vas.
The airtel app is not even showing the vas activated.
Regards
Swapna