Tata Docomo — network not registered. no invalid

My tata docomo no stopped working from past one month. The network always shows not registered, when dialed i get the msg the number is incorrect and when tried complaining in the docomo app it shows number incorrect.
I have connected this no with important accounts and i need it. I didn't get any prior msg about stopping the service for this number ([protected])
From docomo. Please do the needful as i am not able to operate my bank account.