There is no syntax theme defined (see unknown in the status bar). It seems the detection didn't work, or you don't have syntax files installed for some reason.
Press Ctrl + E, type set filetype python then press Enter (or set filetype py, I forgot).
What version are you using? If you previously installed micro 2.0, but then went back to using 1.4.1, you should remove the option filetype from ~/.config/micro/settings.json (delete the line with "filetype": "unknown").
If you are ysing termux then first do set colorscheme default and restart micro then it should work. Termux here is the curprit as this has happened to me many times
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If you are ysing termux then first do
set colorscheme defaultand restart micro then it should work. Termux here is the curprit as this has happened to me many times