I have a subscription with the App calm that is coming due and I cannot open the APP on my computer

Hello ~ I see calm apps for iPhone and iPad in the App Store but take a look here for changing payment. Add new one and then remove the old:

Change, add, or remove Apple ID payment methods

~Katana-San~

Hello ~ What happens when you try to open it? Have you been able to open it before?Post back with more details?

~Katana-San~

There doesn't appear to be a Calm app for the Mac. If you subscribed directly through Calm, start here:

https://www.calm.com