You can see your Offer Wall rewards by selecting the app menu in the upper left corner, then select "Status". There you can see your "Completed" and "Uncompleted" actions.
In case you have not received DENT from a completed action, you can contact Fyber Support by selecting "Uncompleted", then "REPORT".
Please keep in mind that it can take up to 24 hours for DENT to be credited to your account. Please also note, due to Fyber being a 3rd party provider to our platform, DENT Wireless is unable to assist in Offer Wall account-related matters.