Apple/Google handle all payments/refunds and subscriptions, not muzmatch. Only a customer can cancel a subscription - we are not able to ourselves.
Note a trial subscription must be cancelled upto 24 hours before it expires in order to not be charged/renewed.
A free trial can only be purchased ONCE per Apple/Google ID as per their terms.
Also remember - deactivating your muzmatch account does not automatically cancel any subscriptions. You must follow the below instructions as they are handled independently by Apple/Google.
Once cancelled as below, your muzmatch app will still show you as a premium member until the expiry date of the subscription or trial.
Settings → [your name] → iTunes & App Store
View Apple ID, you might need to sign in or use Touch ID
☰ Menu → Subscriptionsand tap on muzmatch
Yesto confirm the cancellation