Idea Cellular — Changing idea rules

Address:

India

I was sent some sms that some details are to be submitted to nearest vi store for verification . I am a final year student and my number is linked to all bank accounts. That is why i didnnt read those sms and they just deactivated my Sim card without calling/informing. And now they say that if the number is not sold to somebody else then only i will get it back and that also will be postpaid for 4 months each 400 +taxes(80) and 300 some other fee
The shop keepers arent coordinting properly and not giving one single response on the issue.
They keep changing their statements some day they say that it will just be billing some day they say that if it isnt sold to somebody then i will get it back
How can you sell my number to somebody else within 5 days?