Mobile Service — Disconnect without notice

Address:

South Delhi, Delhi

Hi,

I have vodofone prepaid mobile number. My services have been disconnected as according to them "I am an non-user". I don't understand why? Without giving any notice via SMS or email, how can they do so? When I try calling their customer care, it takes ages to get connected and talk to someone and then they disconnect without answering the query.
Please suggest what should I do?

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Neeru