@Beka0911
Hi there,
Each offer on the offerwall has a number of requirement you need to meet, so it could be that you didn't fulfilled all requirement. If you are sure you did and Fyber doesn't want to accept your fullfillment of that offer, then you will have to contact our customer support at https://support.onlinesoccermanager.com/hc/en-us
Make sure to provide as much details about the offer as possible and include all communication between you and Fyber about that offer.