Respected Sir/ Madam,
This email is in reference to the credit card that is being used by you which is issued to you in the name of ____________________ (name of credit card user) bearing credit card number _____________ (mention credit card number).
This is to inform you that the payment of _____________ (amount) for your credit card is due on date __/__/_____ (date). You are requested to kindly proceed with the payment on the said date in order to prevent any impact on your CIBIL score/ credit report/ any other. Please ignore if already paid.
[Digital Signature – if applicable]
____________ (Contact details)