All your purchased gift cards are accessible in your "Past Purchases" found in the menu button (☰). If they're not in the "active" tab, try under the "spent" tab.
This article also contains information on the following:
Updating My Gift Card Balance
Click on the gift card you want to update. You may be prompted to enter your 4 digit passcode.
Click on "Update Balance" found at the bottom of the screen. If you know you've spent the whole amount, enter "Mark As spent", which puts the gift card under the "spent"tab.
You can also "enter the amount spent" if you didn't use up the whole amount, or you can simply "enter the remaining balance". Click "update" and then "done".
This tracker only helps you keep tabs on your gift card balance. The actual amount in the gift card may differ. To check the actual gift card balance, you can Google the gift card balance checker of your specific merchant. Please enter the gift card number and pin shown in the Fluz App.
I mistakenly marked the gift card as "spent"
That's okay. Mistakes happen. Simply find that gift card under the "spent" tab.
Click on "Update Balance" found at the bottom of the screen, then click "undo". You should find that gift card back on the "active" tab.