To redeem your Mobile Legend Gift Card code, you need to follow these simple steps:

Log onto the website of MLBB: https://m.mobilelegends.com/en/
Find the Redeem button on the right corner and click it.
Enter your Game ID and click the Send button. Then you will receive a verification code in your in-game mailbox.
Enter the code you receive from the in-game mailbox.
Finally, enter the 17- digits redemption code and click Redeem.