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President Trump tweeted Tuesday that a newly revealed five-month gap in text messages between FBI “lovers” Peter Strzok and Lisa Page is a huge story, saying the missing messages cover a “prime” period of time.

The officials, who once served on Special Counsel Robert Mueller's Russia probe, already were under fire for sending anti-Trump messages during the 2016 election. It was revealed over the weekend that a big chunk in the records is missing, supposedly due to a technical glitch.

“In one of the biggest stories in a long time, the FBI now says it is missing five months worth of lovers Strzok-Page texts, perhaps 50,000, and all in prime time. Wow!” Trump tweeted Tuesday morning.

Despite Trump's tweet, it is not clear how many texts are missing. Roughly 50,000 have been recovered, spanning a two-year period between July 2015 and July 2017.

But messages between Dec. 14, 2016 and May 17, 2017 are missing.

The revelation of the missing messages between Strzok and Page, who both worked for a short period on Mueller's team, came in a DOJ notice to congressional lawmakers.

“The Department wants to bring to your attention that the FBI’s technical system for retaining text messages sent and received on FBI mobile devices failed to preserve text messages for Mr. Strzok and Ms. Page from December 14, 2016 to approximately May 17, 2017,” Assistant Attorney General for Legislative Affairs Stephen Boyd wrote to Senate Homeland Security Committee Chairman Ron Johnson, R-Wis.

“The FBI has informed [the Department of Justice] that many FBI-provided Samsung 5 mobile devices did not capture or store text messages due to misconfiguration issues related to rollouts, provisioning, and software upgrades that conflicted with the FBI’s collection capabilities.”

“The claim that five months of critical evidence went missing due to a technical glitch is really hard to take at face value,” a source from the House Permanent Select Committee on Intelligence told Fox News.

As the president noted, the five-month window covers a crucial time.

MORE THAN 50,000 TEXTS EXCHANGED BETWEEN FBI OFFICIALS STRZOK AND PAGE, SESSIONS SAYS 

On Jan. 11, 2017, BuzzFeed News published the now-infamous, and largely unproven allegations in the anti-Trump dossier -- compiled by ex-British intelligence agent Christopher Steele, commissioned by opposition research firm Fusion GPS and funded with help from Hillary Clinton’s campaign and the Democratic National Committee.

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Former National Security Adviser Michael Flynn, at center, pleaded guilty to making false statements to the FBI as part of Special Counsel Robert Mueller's investigation. (AP)

On Jan. 20, 2017, the president took the oath of office.

Four days later on Jan. 24, National Security Adviser Michael Flynn had an interview with Strzok, in his capacity as an FBI investigator, and other officials from the bureau. Flynn, who has since pleaded guilty to making false statements to the FBI regarding his communications with Russian officials as part of Mueller’s investigation, was fired from the White House on Feb. 13, 2017.

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James Comey was fired from his post as FBI director on May 9, 2017, following his handling of the Clinton email probe. (Reuters)

On March 2, 2017, Attorney General Jeff Sessions recused himself from “any existing or future investigations” regarding the 2016 presidential campaign or Russia, due to his involvement with the Trump team.

On March 4, 2017, the president tweeted that former President Barack Obama improperly was surveilling Trump Tower before the election by having his “wires tapped.” The president called it “McCarthyism,” and questioned the legality of Obama’s alleged actions, comparing it to “Nixon/Watergate.”

On May 9, 2017, Trump fired FBI boss James Comey.

On May 17, 2017, Deputy Attorney General Rod Rosenstein appointed Mueller as special counsel to investigate Russian meddling and potential collusion with Trump campaign associates during the 2016 presidential election.

Deputy Attorney General Rod Rosenstein AP

Deputy Attorney General Rod Rosenstein recommended the president fire FBI Director James Comey. (AP)

When asked Monday whether the FBI “failed to preserve” text message records on similar “Samsung 5” devices belonging to any other FBI officials during that time period, the FBI told Fox News they had no comment.

A Justice Department spokesperson also told Fox News that the department’s Inspector General Michael Horowitz did not have any of the text messages from that five-month window.

Sessions, in a statement to Fox News on Monday evening, committed to figuring out what happened.

“We will leave no stone unturned to confirm with certainty why these text messages are not now available to be produced and will use every technology available to determine whether the missing messages are recoverable from another source,” Sessions said. “If we are successful, we will update the congressional committees immediately.”

Fox News’ Jake Gibson contributed to this report.