In a direct message with the Mio bot, send "menu"
Select My Conversations.
Find the channel you want to deactivate and select View.
Select Deactivate at the bottom.
If you don't see the option to deactivate a specific channel, you must contact the channel owner instead.
Find the channel owner in the same message from the Mio app from Step 1.
Select Yes. You have deactivated your channel.