When placing chords manually, don't use square brackets.
Square brackets fix the chords to a certain position in the lyrics.
Example: [Am7]Some [D7]lyrics
Result:
Am7 D7
Some Lyrics
Now what happens if the chord is wider than the lyrics? Example: [Amaj7/G]Some [D7]klyrics
Result:
Amaj7/GD7
Some Lyrics
Stage Traxx will add a bit of space in the lyrics. Just enough to write the chords. In your example you have only a single whitespace between two chords.
So if you want to write only chords in a line. Just omit the square brackets. If you want to keep using square brackets and need to position two chords with a little space, add the space inside the bracket: [Am7 ] [D7]