MaizieD Jane43 That tweet by Miller. is the subject of an article in the website Snopes. It is interesting to read what they say about it. Near the end of it they say:-
"To recap our analysis so far, the claim stemmed, in part, from reporting by Broadwater, a New York Times journalist, who said Miller issued a memo that prohibited DCNG from using weapons during the upcoming pro-Trump events without his approval first.
While no evidence exists to cast doubt on the legitimacy of the document displayed in the tweet, we sought to independently verify its authenticity. Citing the Freedom of Information Act, Snopes on Feb. 3 submitted a request for a copy of the Jan. 4 record from record-keeping centers within the National Guard and Department of Defense. The agencies have not yet fulfilled that request.
www.snopes.com/fact-check/national-guard-capitol-riot/