This casino only seems to have been around for a couple of months and doesn't have much traffic. It might be due to their inexperience that they assumed you were using automation. If it was $13,533 in bets in 20 minutes, that would not be unusual even if you started with a low balance of a few hundred dollars. The only thing that is kind of a red flag is that you chose to create a scam accusation without even attempting to resolve this through the method they suggested. That still doesn’t imply that you are guilty of wrongdoing. Betflexi should provide more details about what was the suspicious activity in 20 minutes that they banned you for.