Purchased via Stitcher.com:
Go to www.stitcher.com and sign in
Click on the profile icon in the upper right hand corner and select "My Account"
Click "Update" under current plan
Check the cancel box and click on "Update"
Important: When you uninstall the app, your subscription won't cancel unless you take action.
Purchased via Apple/iOS:
Stitcher does not have access to the Apple billing system, so we're unable to assist with managing or canceling subscriptions made through the App Store.
It's also important to note that uninstalling the Stitcher app does not automatically cancel your Stitcher Premium subscription through Apple.
For steps to manage or cancel a trial or subscription from your preferred device, view Apple's See or cancel your subscriptions steps.
You can also contact the Apple support team directly for further assistance.
Purchased via Play Store/Google:
Open the Google Play app
At the top right, tap the profile icon
Tap Payments & subscriptions Subscriptions
Select the subscription you want to cancel
Tap Cancel subscription
Follow the instructions
For more info: Cancel subscription Google Play Store