Hey! My number too was demo 441 and was deactivated without prior notice on Feb 4 2011. On sending query4 times, first response was AIRTEL people told that I have requested for a plan change through SMS, second time they said that I recharged with booster 22, third time they said that I have wrongly pressed an option from a telemarketing call and finally the fourth time they said that the plan was withdrawn 2 years back. I was not satisfied with this response and wrote to email@example.com and again to nodal officer. I have recorded all these interaction and have them as evidence. To the nodal officer I explained the matter clearly and proved that the mistake was not on my side. They have again given my plan back on 1st Mrach 2011.