You may refer to the below steps were to check your Shopee Voucher has been stored in your Shopee App.
Step 1: Click on "My Vouchers"
Step 2: Copy your voucher code from your Shopback app and paste it under "Input Voucher code"
Step 3: Once you have input your code, it will be stored under your "My Voucher" > "Shopee Voucher"
If there's an error while inputting the code, please check if the code is already in your "My Voucher" section.
If the voucher is not in your "My Voucher" section, please take a screenshot of it and send it to email@example.com and our customer service team would be glad to assist you further.