We have no access to any subscriptions created through Sling. A subscription made through HMN will not have access to a subscription created on Sling and vice versa.
For any and all billing issues through Sling subscribers can cancel online. Log onto Sling.com, click on My Account and change subscription, you must contact Sling.
You can contact Sling customer support through https://help.sling.com/. Be sure to tell the Sling agent that you have Hallmark Movies Now through your Sling package.