Subscription shows expired
When you have an issue with a subscription on an iOS device when you believe it is active, it usually means that iTunes had an issue connecting to your device during renewal, you changed your Apple ID, or there is a problem with your Apple account such as your credit card on file, etc.
To rule this out, first check that the subscription is still valid with Apple: https://support.apple.com/en-us/HT202039
If it is shows that it is still active in the above link, try doing the following:
1. Sign out of iTunes App Store on your device through the device settings
2. Reboot device
3. Open device settings and sign back into your iTunes account
4. open PostureScreen, click Upgrades, scroll to the bottom and click Restore Purchases
5. On that screen does your subscription now show active?