Since Washington, D.C. does not have a governor, President Trump has 100% authority over National Guard. Mayor Muriel Bowser's tweets are therefore just simply requests which are masked in a way that many people are fooled to think she actually has any kind of authority over NG. Her kicking NG out from the hotel they were staying in is also very questionable and I'm fairly certain she didn't actually have legal ground to do that.
https://twitter.com/MayorBowser/status/1269037339994660864
https://twitter.com/MayorBowser/status/1269037343605915650
https://twitter.com/MayorBowser/status/1268895206713307138
https://www.breitbart.com/politics/2020/06/05/national-guard-members-look-for-place-to-stay-after-dc-mayor-kicks-them-out-of-hotel/#