5. Wait for hold calls

If you enabled session (and most likely you should have), we send a hold call to the server when the user clicks on a seat.

It's important to wait for all hold calls to have finished before allowing the user to continue to the next step in the booking process.

There are two callbacks that help with this: onHoldCallsInProgress and onHoldCallsComplete.

You should disable your 'next' button onHoldCallsInProgress, and enable it again onHoldCallsComplete.