My iPhone isnt working with messages. The messages tend to get backed up and I receive them all later... The phone won't send iMessage during this time period... What do I do?

Question

The messages in the phone don't load until hours after they're received and seem to get overloaded very easily

Answer 1

What would you do for transportation if you drove your car into a tree and had to wait while it was fixed? You'd need to rent, borrow or buy another car, no? The same applies to your phone. This is not Apple's problem; if the service center does not have replacements in stock for immediate swap-out, then it's up to you to provide a backup device or do without.
If you're in a country where Apple provides direct service for iPhones, you may be able to call Apple support and arrange for advance replacement, where they send you the replacement phone and then you send back the old one. Apple offers such service in several countries, though you have to pay an extra fee for the service. If not, then you'll just have to wait for the service center to get in the replacement, and will have to arrange an alternative to use during that time.
Regars.