[BUG] Cancel Registration link does not work when event is at full capacity

[DykstraSound]

Description

When an event registration is at full capacity, clicking the Cancel Registration link in an existing registration does not take the user to the cancellation page.

Instead, it redirects to the Over Capacity page, preventing the user from completing the cancellation.

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Steps to Reproduce

1. Set an Event Instance to full capacity.
2. Locate an existing registration for that event.
3. Click the Cancel Registration link (e.g., from confirmation email or registration detail page).
4. Observe that the Over Capacity page is displayed instead of a cancellation page with a cancel button.

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Expected Behavior

Clicking the Cancel Registration link should:

• Display a cancellation page with the option to confirm the cancellation, even if the event is at full capacity.

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Actual Behavior

• The link redirects to the Over Capacity page.
• No cancellation option is presented to the user.

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Impact

• Registrants cannot cancel when the event is full.
• Prevents freeing up space for other potential attendees.
• Creates additional manual work for event managers to process cancellations.

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Acceptance Criteria

• Cancel Registration link works regardless of event capacity status.
• At full capacity, the cancellation page is displayed and functions normally.
• Tested for:
  • Events below capacity.
  • Events exactly at capacity.
  • Events over capacity (if allowed).

[DykstraSound]

https://youtu.be/HfL2axdNc08

video of bug