I have the same issue with the team command. In my case it will accept the "assign" command with no hitches. But the most I can make it do when saying "team red" for example, is what equates into pressing 'F5'. I've tried adjusting the key release delay to the max in a desperate attempt to get it to register and it still doesn't.
However the program registers the voice command. I don't think it's an in-game issue, there must be something in the program that has gone amiss. Maybe it has something with localization to do?. I'm using a keyboard with a Nordic layout/localization.
EDIT - On further investigation I figured out that by pressing and holding 'shift' as I issue a team select command it selects the whole team of that color.
So I assume it's using the shift+F1-F5 commands. And if that is the case then there might be an issue if the program sends one key at a time when it has to press both 'shift' and F1-F5 at the same time.
TL;DR - The program is sending the "team select" commands in separate-sequence rather than in combination-sequence. In other words: shift, then F1-F5. Rather than the required Shift+F1-F5