DuckDice and Tower.bet are operated by the same people. My guess is they use the same sports betting provider as well. If I were you, I wouldn't deposit anything else into that DuckDice account you have. Maybe they are waiting for you to do that so they can confiscate your money.
If they are accusing you of value betting, it means that they believe that you took (systematic) advantage of higher odds on their website than they were elsewhere. This can be in pre-match or live betting. If the odds of an outcome are higher than the likelihood of that outcome happening, it's considered a 'value bet.' If all or most of your betting history consists of such bets, the bookie probably sees that as an unfair way of playing.
I don't necessarily agree with that, but that's the way it is. I think that if they offer odds of X, they should also pay out all winnings players make betting on those odds. What's the point in offering them if you can get in trouble betting on them. If it was the other way around, and the bookies offered too low odds on an outcome, they sure as hell wouldn't cancel bets and refund players.
I placed games mostly on big market or esports matches, I checked the sport provider, it is Betby sportsbook.
I think it is not fair, they can ban my account and refund my balance, but cannot do it on that way lol.
It is a common practice amongst casino to return your initial depo if you're in the minus PnL or to return nothing if your overall PnL is in the green side. They're here to be fair, to pay what is won fairly and return what's not belong to them [suppose you're in PnL negative, thus eligible for initial depo]. Again, if you're willing for me to be your eyes and see evidences they have for you [very much likely it'll be under for-my-eyes-only], kindly provide your login details to me, you can PM me that if you prefer the info to be private, I'll reach my contact come Monday to consult with them regarding your issue.