Let's get started from scratch, do you using it on CSGO or CSS?
Now I'm guessing that on CSGO, because at the moment we don't use this plugin on our CSGO servers, so probably this problem occurred directly on the CSGO only.
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Update 02.01.2021
I've reproduced the problem, issue task created on GitHub for
Multi-Colors
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Update 02.01.2021
I've done an update for the CSGO team colors problem,
should works now.
@Razvann. Check it now, if you will be able, please add your translation (by PR) to the branch, I'll merge it.