While navigating and attempting to create a Collection, this is the page that loads. Help.
Make sure the collection exists/active for the store.
Try creating another collection and testing.
Try in another browser and or clear the cache of your current one.
If none of that works contact support.
Hello @JustGenevieve 
I think it was just a temporary issue. Please try again later and it should works.
This is Richard from PageFly - Shopify Page Builder App, I’d like to suggest this idea:
You should check the cache and clean it to solve this problem
Hope you find my answer helpful!
Best regards,
Richard | PageFly