Didn't get your cashback after a qualifying purchase? You can submit a claim in the app.
Go to your Cashback Sock, report the missing cashback and follow the steps. There you select the cashback you missed and claim it.
Please note: you can only submit a claim if the cashback is still valid (not expired) and the transaction has been processed. If the transaction is still being processed, you can't submit a claim yet. Just wait a little longer: in most cases the cashback is credited automatically once the check is done.