Follow this tutorial to link your Debit or Credit Card to your PayPal Account.
1. Log in to your PayPal Account.
2. On top of the menu, click on Wallet.
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3. Click on Link a card.
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4. Click on Debit or Credit Card or any other appropriate option displayed in your PayPal account.
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5. Enter your card details and then click on Link Card.
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6. It may prompt you for card verification, such as a one-time password, or use available verification methods. After you complete it, your card will be added successfully.