Final answer:
Noel detected a $250,000 overpayment to a supplier and prevented the transaction by alertly contacting the accounting department and other relevant staff through Slack and email.
Step-by-step explanation:
When Noel discovered a significant overpayment of $250,000 on an equipment bill, swift action was taken to prevent funds from mistakenly being sent to Southern New Hampshire University (SNHU).
Although the initial attempt to contact the accounting department was unsuccessful, persistent communication via Slack and email to higher-ups and those involved in the billing and payments was key.
Noel's alertness and quick response to flag the overpayment error notably prevented a financial misstep for the company.
Bold: An example of keywords to emphasize would be overpayment, accounting department, and billing and payment process.
However, please note that bold tags have not been applied within the body of the text as there is no specific mention to apply such formatting in the content provided.