Hello Vasant. 

You will have to confirm with the bank whether the amount is debited or not. Also you will have to write an email to the NTA regarding the same. 

I would suggest you to wait for a while before paying again. NTA have noted the payment errors through echallan and are working on to refund the unsuccessful payments. 

Dear Vasant, please check with your bank if the payment went through. If it has gone through, ask them for the right reference number. If it hasn't gone through, please select a different mode of payment like NetBanking or Credit or Debit Cards. There have been reports of payment issues with E challan.