Yes. Here is the fix.
Log into your MyATT account.
Go to myAT&T, Wireless, Enhanced Services, 3G Microcell.
Delete all numbers except the master number (because you can't). Reload all numbers and save.
Reset microcell by pulling power cord and reinserting after 10 seconds.
Wait about 5 minutes and do a hard reset on all phones trying to connect to microcell.
Rejoice at your success.