In order to request support for a specific goal, go to the "My Games" section and click into the mobile game you're requesting support for. You should see an option to request support at the bottom of the Game Progress page.
Click the button to request support and follow the instructions on screen. These instructions may differ, depending on which Rewarded Play Partner is managing the specific mobile game offer. You may need to provide information such as your email address associated with your Capital One Shopping account and in-game screenshots that prove that the goal was completed.