Stripe Subscription Not Working

I use Bubble’s Stripe plugin to sign users up for subscriptions. Everything was working fine, but now for some reason the button that calls the command to “sign user up for a subscription” does not redirect the page to Stripe’s payment form like it used to. Instead, the page just shows a loading bar to completion and then nothing else happens.

My product IDs link to the Live Version, so it shouldn’t be a problem of live vs test keys. What’s the problem here?

The user has to be logged in when adding a subscription to a user.