I can't add debit card on account.

Please review this support article→Payment methods that you can use with your Apple ID - Apple Support

Also note A “card declined" message means that the issuer of the credit or debit card you have on file in your iTunes account rejected an account confirmation. It is not an Apple problem; Apple is just passing through the message from your issuer. There are a number of reasons the charge or verification might be declined:

• Apple is not allowed to accept credit or debit cards in your country
• The card is not recognized in your country
• Insufficient balance or account in arrears
• Account suspended for suspected fraud (not necessarily by you)
• Error in card number
• Wrong expiration date
• Wrong security (CVV) code
• Address in your iTunes account does not match exactly the billing address for the card
• The card was not issued in the country of the iTunes store
• You are connected through a VPN provider that does not terminate in the country of the iTunes store you are connected to.

Here is additional information from Apple→If your payment method is declined in the App Store or iTunes Store - Apple Support