1. Please log into your channel and click Settings.
2. Now click on the Channel managers button.
3. Once you've selected the Channel managers button, you should see a set of options. To remove the channel manager, Just click on the "Revoke" button.
You will see the below screenshot when the "Revoke" option is selected.
When revoking a user you will be asked for confirmation. Once this is confirmed, the user's access to the channel will be revoked immediately.
For steps on how to add a channel manager, please go to the article link below: