Please reread the rules.
Including the parts specific to 2 players. (Including the second paragraph of the second column of page 7 of the rules.)
Verify that you read the board as i was at the time of the bug correctly, use a replay if necessary, don't trust your memory.
And verify if someone has already posted the bug
We already have 3 bug reports and additional comments in them of players complaining that they can't use the purple dice even though they have the same number of XYZ crossed as their single opponent.
Including the parts specific to 2 players. (Including the second paragraph of the second column of page 7 of the rules.)
Verify that you read the board as i was at the time of the bug correctly, use a replay if necessary, don't trust your memory.
And verify if someone has already posted the bug
We already have 3 bug reports and additional comments in them of players complaining that they can't use the purple dice even though they have the same number of XYZ crossed as their single opponent.