In broadcasts, the Manage Subscriptions link needs to be added so your contacts can manage their subscriptions. 

To do so, you can do any of the following when scheduling a broadcast:

1. Check the Manage subscriptions link option under Messages / Layout

2. Place the Manage Subscriptions link anywhere in the message content using the dynamic tag {MANAGE_LINK}

An unsubscribe link does not work for broadcasts because the contact could have many subscriptions. It should only be used on autoresponders.

arpReach does not have a global unsubscribe, but rather manage links.