I would try submit a "ticket" at support page 

was it in clan chat? if not i'd say best way to deal with it is leave. i've met awful people in this game and i just ignore them. not worth the stress.

On the official discord, there's a channel called #chat-reports. Take a screeshot of that player being toxic and a closer one where you can see their clan (if they have one), and me, or another mod, will submit it to support to get him banned

tigerspawn1 said:

How do we get a person banned from a chat channel. We have a very toxic person in chat. He constantly causes issues. What can we do? He is ruining chat for everyone. 

clan chat to keep your group chatting together of course 

Global chat. Well every day I log on there is way more than 400 global chat channels to choose from which you can also pick and/or change to at any time

Let your friends know where you will be and get them to join you on that # channel. It would be very hard for a trouble maker to randomly follow you through that many channels. near impossible I would think