This the only I got from support chat
And when the issue was not fixed, did try logging out from your account and logging back in?
If you tried all of this and still, the issue with the session expiration did not still work, then If I was in your shoes, I would believe that bc.game cheated you out, they possibly knew that last game was going to lose and if you have your way, you may possibly want to cash out in order not to lose the entire parlay ticket, so they purposely blocked you access to the sports betting session so you don't have any means of cashing out.
If you actually did lose that game, I did suggest you take the issue up with them, and atleast, get your initial bet back, this is if you have all the evidence to prove your case though.
This isn't just what you think. The problem was on their end. I tried everything you suggested before posting this, and still the problem persist. I don't think they will cheat on me since my bet is only worth $1.5. But I don't know how much I can cashout that time since I can't access my active bets because of this problem. I'm not the only one experienced this at that moment. The whole sport chat discussing this problem at that moment.
Here's the proof: I got 8 out of 9 but didn't cashout because of this problem.
So, if you have this information, and you don't mind, please share.
And secondly, I am also glad to know that the issue was not peculiar to you alone, since you said alot of players were also complaining about the same issue in the chatbox, this also, together with the fact that your initial bet amount is something you can easily forgo, should help you decide whether you are taking the matter up with bc.game, or you just forget about it.
Personally, I would suggest you just forget about it, shits happen and glad the amount involved wasn't much.