Phyllis Humphreys, 76, waited with her husband last week in a line of cars in Clermont, west of Orlando, that spilled onto Highway 27. They had scrambled into their car and driven 22 miles after receiving an automated text message saying vaccine doses were available. But by 9:43 a.m., the site had reached capacity and the Humphreys went home with no shots.

“We’re talking about vaccinations,” said Ms. Humphreys, a retired critical care nurse. “We are not talking about putting people in Desert Storm.”…

Palm Beach County was accepting vaccine requests only by email, said the county’s health administrator, Dr. Alina Alonso, after the county’s phone system “absolutely died.” People in the queue were warned that they might have to wait months for an appointment. In the meantime, some wealthy people with connections to health care facilities have been able to get the vaccine more easily.

Adding to the complications, the Florida Division of Emergency Management announced on Sunday that its coronavirus testing and vaccination site at Hard Rock Stadium in Miami Gardens — the recent scene of long lines of people awaiting vaccination — would be shut down for much of Monday to make way for the College Football Playoff national championship game.