TOPIC: Simultaneous Registration and Selection Limits Issue

When multiple people have started a registration within the same time-frame, they are able to select options whose limits may have expired.

Example:
X has a field selection limit of 1.
User A and User B simultaneously begin a registration.
Both User A and User B select X.
Both User A and User B receive a notification that X has been applied to them and charges the corresponding amount for X.

So... How do I get around this? Or what do other people do? Any suggestions? This has occurred twice for me this morning and we aren't even close to our busy time yet.

DT 2.8.2a