Appointfix
Appointfix subscriptions are charged through the App Store or Google Play, so you’ll need to update your payment method there.
On your iPhone, iPad, or iPod touch:
For more details visit Apple’s support page: https://support.apple.com/en-us/HT201266
On your Android device:
For more details visit Google’s support page: https://support.google.com/pay/answer/7644063