They do not have the ability to fix this. My wife's data plan is capped at 500MB and when it runs out iMessage does not work. She turned off iMessageing and days later when she still reported that she wasn't getting texts. The Apple tech said that she should tell people not to reply to a thread and to start a new one. She uses her phone for her business and she can't preemptively blast text over 150 contacts not to reply to an active thread, but to start a new one. Her iPhone contacts don't even understand the issue. Now she has to upgrade to an unlimited plan or risk missing messages. Apple has broken text messaging for anyone who uses an iPhone.