Stripe subscribe the user to a plan: Cannot specify proration date

I want the user to update subscription quantity and I’m doing it by using “subscribe the user to a plan” and then updating subscription. (I could use the “update the subscription” but I’m doing it like this because I can’t find and get the subscription item ID: Stripe - Update subscription quantity). This is it:

But I get this error when sending, why?

Skärmbild 2024-03-25 103043

What I’m trying to do is to let users create teams and pay per user added to their team. So when the user add a member to the team I let the user update the subscription quantity to equal the number of members. Let me know if anyone know a better way to do this.

Is that the Bubble stripe Plugin? I’d expect it is…and it would seem they did not build it out properly, because in the screen shot there is no area to input the proration date, and that particular parameter is the problem, and the problem is that the value needs to be between certain dates, likely the dates of the start and end of the current billing period, and there is good chance the plugin is using the wrong values to send, where the plugin is likely sending values as milliseconds, but Stripe requires seconds.