Oh man, please read carefully
1. Turn off your phone
2. Press & hold "Volume+" & "Volume-" & "Power Button"
3. When mi logo show up, release "Power Button" but don't release "Volume+" & "Volume-" until twrp appears
What do you mean? I can enter twrp on 22.214.171.124 (ofc with key press combination)
What rom are you using? AFAIK @ingbrzy uploaded 3 released.
1st = installation trouble
2nd = with fix installation <-- I'm using that
3rd = I don't know what's different with 2nd (Not trying yet)