In Nigeria, if you wish to sell an Amazon gift card worth 200, there are several steps you can take.

First, you need to find potential buyers. This could be through various online platforms where people are interested in purchasing gift cards. You can post about your offer on relevant Nigerian forums or social media groups dedicated to such transactions. Make sure to clearly state the details of the Amazon gift card, including its value of 200, and any terms and conditions you have for the sale.
Once you have found a potential buyer, it's crucial to ensure a secure transaction. One way is to use a trusted third-party escrow service if available. This helps protect both you and the buyer. If not, you can agree on a payment method that is safe, such as bank transfers. Provide the buyer with accurate instructions on how to transfer the money and ensure they understand the process.
After the payment is received and verified, promptly provide the Amazon gift card details to the buyer. This should include the card number, PIN (if applicable), and any other necessary information. Make sure to communicate clearly throughout the process to avoid any misunderstandings. By following these steps carefully, you can successfully sell your 200 Amazon gift card in Nigeria.