"the FBI, for technical reasons, had been unable to preserve and retrieve about five months' worth of communications."

Eric Tucker reports in AP,

The Justice Department has turned over to Congress additional text messages involving an FBI agent who was removed from special counsel Robert Mueller's investigative team following the discovery of derogatory comments about President Donald Trump.

But the department also said in a letter to lawmakers that its record of messages sent to and from the agent, Peter Strzok, was incomplete because the FBI, for technical reasons, had been unable to preserve and retrieve about five months' worth of communications.

In addition to the communications already made public, the Justice Department on Friday provided Johnson's committee with 384 pages of text messages, according to a letter from the Wisconsin lawmaker that was obtained by The Associated Press.

But, according to the letter, the FBI told the department that its system for retaining text messages sent and received on bureau phones had failed to preserve communications between Strzok and Page over a five-month period between Dec. 14, 2016, and May 17, 2017. May 17 was the date that Mueller was appointed as special counsel to oversee the Russia investigation.

The explanation for the gap was "misconfiguration issues related to rollouts, provisioning, and software upgrades that conflicted with the FBI's collection capabilities."

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