Make sure you are online and you check in when the tourney starts. I know you asked to be in since the start, but I can't eliminate anyone else in order to accommodate you. You will be subbed in when someone fails to check in. I'm afraid there should be quite a few of them...
If you think that a crucial skill of yours fails or misfires, call for the match to be stopped. Alternatively you can play through the match and then raise the issue with the organizer running your match, it will be their call in the end either way. If the organizer decides that the misfire/skill fail did not affect the outcome, then you will not be allowed to replay it. Long story short: The organizer is the referee, they call the outcomes
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