Step 1. Check Active Contacts
Contacts can only be active in one campaign at a given time.
When a contact has a green dot next to their name, this means this contact is active in a campaign.
As long as the contact does not have the green dot next to their name, they are not active in the campaign and can be added to a new campaign.
Please see the attachment/screenshot below for reference:
Step 2. Stop Outreach
Navigate to the Campaign you'd like to remove the contacts from.
Select the checkboxes of the contacts.
Click 'Stop Outreach'
These contacts will no longer be active in the campaign.
Step 3. Move the contacts
While to the Campaign you'd like to remove the contacts from:
Select all contacts you'd like to move
Click 'Add to Campaign'
Select the Campaign you'd like to add the contacts to.
Now your contacts are active in the new campaign. 🎉