No Confirmation on Booking Page

Our bookings page no longer displays the booking confirmation on a consistent basis. After clicking the submit button, the page just seems to hang. At some point the process does finish as evidenced by the updated database and sent email confirmation. After 20 or 30 seconds if you click again, it will tell you you are already registered for the event.

We have checked the integrity of the database and all seems fine

What process is going on after clicking on the button that could hang the system and not fully complete the process? How would one suggest we troubleshoot the problem?

Thanks in advance for any help.

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