Trai — tata teleservice (tatadocomo mobile service)

Sir i am using tatadocomo mobile service from the past four years and paying my bills on time. About a weeks back i am unable get any signals, as for my knowledge i have changed the aim card.
Other service provider signals are available and i am able to talk. I think docomo discontinued the service without customer notification without any notice.
Many of their stores were closed / not lifting the calls. Unable to contact their customer care. When calling from other network we getting you have insufficient balance. Since there is no network unable do the port change. This no is linked to
Banks, aadhar, personal nos. Look forward your advise how to overcome this issue.

Thanking you
Rajkumar
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