Dear [Organizers],
I am writing to express my sincere regret that I am unable to attend the [Name of Concert] featuring [Name of Singer] that is scheduled for [Date & Time]. I had purchased tickets to the event without knowing that I would have an exam the next day, and had been looking forward to attending.
I am aware that the ticket states that there is no refund or exchange, but I was hoping that you might be able to help me out in this difficult situation by exchanging my tickets for another date. I am free on [Suggested Date(s)] and would be more than happy to attend on any of those days.
I understand if this is not possible, but I wanted to reach out and ask for your assistance. I look forward to hearing from you soon.
Sincerely,
[Your Name]
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