IDEA POST PAID
Fraud and not atarting numbe

I had brought 1 idea postpaid number-9165155000, from idea head office at rs600, that time their executive said number will start in evening, than i called her in evening to start the number, than she said server is down number will start tomorrow, i said ok . but next morning she is calling me n saying if you wanna start number 900rs more you have to pay. Now what should i do now please help