So, I guess the problem here was that OP was not eligible for the promotional bet in the first place, thus revoked.
Thank you for your response, but if OP was not eligible for the promotional bet, they should have excluded him from the beginning, thus the question, was OP ineligible for the promotional bet or the winning bonus, i would say it is the latter, and they should provide him with the reason why he is ineligible for the bonus, and the rules they claim he violated.
The promotion ran from February, it is a long time not to detect that OP was not eligible for the promotion in the first place, but OP was allowed to compete, playing with a minimum of $20 and a ninimum odd of 3.0 on CL and Europa League knockout matches. I think it is unfair OP was allowed to take part in the competition, only to win something and then the winnings taken away.