Without giving you much stories, let’s hit the hammer on the nail.
Here’s is a confirmed step to get the mtn auto renewal feature deactivated.
Send ‘NO’ to 21600 and you should get a successful message.
How To Cancel Airtel BlackBerry Service Auto-Renewal
As at the time of posting this, i don’t think Airtel automatically renews a bb package, but cancel your bb subscription when its about to expire by simply texting ‘Deactivate to 440‘.
How To Cancel Glo BlackBerry Service Auto-Renewal
Simply text ‘Cancel’ to 777
How To Deactivate BlackBerry Internet Auto-Renewal Service On Etisalat
Simply text ‘stop’ to 229 or dial *229*0#
Hope this helps?