Hello Aspirant,

There might be any technical error with the website or there might be your network problem.

If you have paid the registration fee successfully than your fee receipt will be generated automatically.

If amount is deducted from your account but still they are asking for payment than you should drop a mail to them with your issue and attach that receipt(if generated).

If the amount is deducted from your account and did not reached to beneficiary's account than it will be returned into your account within three working days.

I hope this information helps you.

Good Luck!!