https://techcrunch.com/2021/01/08/president-trump-responds-to-twitter-account-ban-in-tweet-storm-from-potus-account/

After Twitter took the major step Friday of permanently banning President Trump’s @realdonaldtrump Twitter account, the President aimed to get the last word in through his government account @POTUS which has a fraction of the Twitter followers but still offered the President a megaphone on the service to send out a few last tweets.

The tweets were deleted within minutes by Twitter which does not allow banned individuals to circumvent a full ban by tweeting under alternate accounts.