They blocked my bet
Can you elaborate on this any? What event did you bet on, how much did you want to bet, was the bet accepted and then cancelled or was the bet not allowed to be placed at all?
If you tried to bet 100% of your deposit and the casino turned away your action, then I'd argue you met any wagering obligation. If you can prove that happened, I'd support a flag.
That said, the only reference to a wagering obligation I see on the duelbits.com site is the following:
After a user deposits funds to Duelbits using any depositing option provided by the company, except CS:Go Skins, there is a minimum percentage of the amount that must be wagered until a withdrawal for the said funds is requested, otherwise the company reserves the right to ask for any additional KYC documentation and freeze the user’s funds until the KYC requirement is fulfilled.
Did they ask you for KYC documents and did you cooperate? I would ask them to point out the specific part of their agreement that they are trying to enforce. If it is this section, ask them to define "minimum percentage" and consider trying to meet that obligation. If you have provided KYC documents, then I'm having trouble seeing their position. I would consider supporting a flag based on this interpretation of their terms of service if you wanted to make that argument.