How to correctly implement the Billing API in my app?

Hi,

I’m trying to implement the Billing API in my app and I’m having trouble with the confirmationUrl that is generated when I create a subscription. I’m trying to redirect my app to that URL when someone creates a subscription, but after that I’m getting the error "mystore redirected you too many times". Am I doing this wrong? Because I just went to the URL manually and it works fine, and the subscription appeared in my dev profile.

I’m not very clear about this step, and I’m a little stuck in this.