The present disclosure is related to a field of payment transactions using a card that discloses a computer-implemented method and a system for restricting a transaction while using a payment card. A card processing server may receive card details, a transaction amount, a flag, and signature data of the payment card from a remote terminal upon initiating a transaction using the payment card. Further, the card processing server validates the payment card based on the card details and the signature data of the payment card and thereafter determines a value associated with the flag upon successful validation. The value associated with the flag indicates one of two conditions, e.g., a true condition and a false condition. Based on the condition indicated by the flag, the card processing server performs one of a first action and a second action related to either processing or declining the transaction.