Sounds like it could be an issue with the Payment Agreement. Incoming first year students need to accept it to confirm they are coming to McMaster and to lock in their choices, etc. You're sure that you submitted the payment agreement, and then clicked the button to save and confirm? It should have a date showing when you confirmed the payment agreement. Don't click confirm again... cause it will re-submit it which you don't want to do if you've already done it.
If you're sure you confirmed the Payment Agreement, then I would call up the Registrar and get them to look at your account as they can see if you've confirmed it, and what is causing the problem... then fix it right away over the phone, which is nice
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