Rs.5 is debited from your UPI linked bank account if E-NACH setup is done using UPI ID during the onboarding process. The refund gets processed within 48 hours from the NACH setup date by respective lender. Lender name is mentioned on onboarding screens and Tata Pay Later dashboard. 

Refund is not applicable for the cases where E-NACH setup is done using Net Banking or Debit Card as no debit happens from your bank account in this scenario.