Reset iphone calendar

Hi! I recently moved from Android to iOS but had an issue with my calendar when it transferred. In G calendar by default, it shows you events for all the national holidays, however when this transferred to my iOS device, it for some reason created the events 10 times each. This only affects the holiday events somehow.

After doing some digging, it looks like it’s the top Calendar category that’s doing it, as when it’s disabled, all my normal events stay but the duplicate holiday events disappear. Notice how 1 holiday event is purple for the holiday category, followed by 9-10 default calendar duplicates.

How can I reset the main calendar to delete all the duplicated events?

Thanks!

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