If you subscribed through iTunes or Google Play:

If you have a coins subscription through iTunes or Google Play and want to cancel it, you will need to cancel it within your phone's app store subscription settings.
You can read the instructions from Apple and Google here:

iOS: https://support.apple.com/en-us/HT202039

Android: https://support.google.com/googleplay/answer/7018481?co=GENIE.Platform%3DAndroid&hl=en

If you subscribed directly with your credit card:

If you have a coins subscription directly through your credit card (not through iTunes or Google play), you can disable your coins subscription by going to your Account Settings > Billing & Subscriptions.

To get to your Account Settings page, log in at locals.com and from your My Newsfeed page, select your name/portrait on the top right and from the drop down select Account Settings.

Then, under the Billing & Subscriptions tab, select the "Manage" button.

Then, you will see the option to toggle off (cancel) auto-renew for your coins subscription on your credit card.