From SpaceNews [spacenews.com]:
In a July 8 statement, the Navy said the fifth satellite in its next-generation narrowband communications constellation, known as the Mobile User Objective System, had expected to reach geosynchronous orbit and a test location about 35,400 kilometers above Hawaii by July 3. But following a successful launch, "the satellite experienced an anomaly that required the transfer maneuver to be temporarily halted," Steven Davis, a spokesman for the Space and Naval Warfare Systems Command, said. He did not elaborate.
Since the event, the Navy "has reconfigured the satellite from orbital transfer into a stabilized, safe intermediate orbit to allow the MUOS team to evaluate the situation and determine options for proceeding," he said.
The satellite, MUOS-5, is a "spare for a system that provides smartphone-like communications to mobile forces at rates 10 times faster than the Navy's legacy satellites." The four primary MUOS satellites are on-orbit and performing as expected.
United Launch Alliance lifted MUOS-5 June 24 from Cape Canaveral Air Force Station in Florida aboard an Atlas 5 rocket in its most powerful configuration, featuring a 5-meter payload fairing, five solid-fueled strap-on boosters and a Centaur upper stage powered by a single RL-10 engine.
[...]
Lockheed Martin is the prime contractor on the MUOS program.
"Nothing is more important to Lockheed Martin than mission success," said Chip Eschenfelder, a Lockheed Martin spokesman. "We are working closely with our Navy customer to determine the cause of the anomaly."
The Government Accountability Office has said the MUOS program carries a price tag of about $7.7 billion.