Idea cellurar
Idea prepaid recharge talk time not credited

I have recharged my Idea prepaid number (9640250766) on 19th May for the offer 75/- through a online portal and i got a sucess message for online portal but i haven't got any talk time even single paisa also.

When i called a customer care people for three time i got three different responses and finally on customer care people told me that offer is valid only upto 18th then i have asked wht abt my money he said i will not be able to get any thing out of that which is very bad and they are not ready to take complaint on this...

my question is do i need to loose my 75/- for nothing .. how insane is this .. if offer is not valid/available it should reject the same and the 75 /- needs to be credited to my account ..

Any one please help me on this...

Thanks

Gupta