How to Activate/De-Activate Missed call alert service in Airtel

THIS INFORMATION'S I GOT FROM THE RESPECTIVE SERVICE PROVIDERS WEBSITE. THE TOLL FREE NUMBERS MENTIONED BELOW ARE SUBJECT TO CHANGE AND THE SERVICE PROVIDER MAY DETECT MONEY ALSO. PLEASE DONT BLAME ME.

What is Missed call alert service ?
It is a service to Get updates of all calls you miss if your phone is switched off or you are unreachable. Next time someone tries to call you while you away you will receive a SMS notification as soon as you are back in the coverage area, or when you switch on your phone.

FOR DELHI, ORISSA, WESTBENGAL, KOLKATA, BIHAR, JHARKHAND, HARYANA, UP WEST, UP EAST,  UTTARKHAND, ASSAM, JAMMU KASHMIR, TAMILNADU, AND CHENNAI USERS.
How to Activate/De-Activate
To activate dial *321*881# and to deactivate *321*883#
Prepaid Charges
Rs. 15 per month

FOR ANDHRAPRADESH USERS:
How to Activate/De-Activate
Send SMS MCA active to 52121 or *132*1881*

FOR KERALA USERS:
How to Activate/De-Activate
To activate, dial *135*2# .To deactivate, dial *135*1#

FOR MP AND CHATTISGARGH USERS:
How to Activate/De-Activate
1. How to subscribe the pack:- By dialing *321*880#
2. Customers can unsubscribe to the pack by dialing *321*883# or by sending STOP to 121 Charges: 1Re on the day of Missed Call.
Customer can also take service by dialing *321*882# which is priced at rs 5 per month.

FOR MUMBAI, MAHARASHTRA AND GOA USERS:
To activate dial 54888 or just dial *321*881# for monthly or *321*882# for Hafta (weekly) Pack.
*321*883# MCA Deactivation Code
*321*884# Rs.30 Advance Rental 3 months
*321*885# Rs.60 Advance Rental 6 months
*321*880 Zero Rental pack (Re.1 on the day customer receives any MCA)

Mode of unsubscription: Dial *321*883#(tollfree) or sms to STOP 121

Prepaid Charges
Rs 15 Per Month,Rs 5 for 7 Days

FOR PUNJAB USERS:
To activate press
Monthly Pack *321*881#,
Hafta Pack *321*882#,
3 months pack *321*884#,
6 months pack *321*885#

Prepaid Charges
Subscription: Rs 15/month, Rs 5/7days,Rs 30/90 days, Rs 60/180 days