Enabled the managed pricing once, can't go back to manual pricing anymore.

[schokola]

Hi, for the first time, I am releasing my app to public, but I'm encountering this problem regarding pricing and I've been stuck for a week. 

At first, I thought managed pricing seemed straight forwarded and the app was simple, so I selected managed pricing. 

Later I figured that there are not much documentation regarding how I would check the active subscription of the store for many reasons. (what would be the value I put in the plans field on billing API. I see no active subscription while I'm on a dev store testing an app. Is this normal for dev? or is this an error? Couldn't find any documentation)

So I decided, I would use manual pricing since there are plenty of documentation and examples for that. 

However, I'm encountering a problem using Billing API. 

On the app distribution setting from Shopify partner, I set the pricing method to Manual pricing, deleted all the pricing I've created for managed pricing. 

When I try to run Billing API such as billing.request(), I get the following error

Managed Pricing Apps cannot use the Billing API. 

No matter how many times I check the App Listing Submission page, I have it on manual pricing. I even changed to managed -> click save -> change back to manual -> click save. Still not luck. 

I don't know if its because the app is not released yet, or its because its running on npm run dev, or it's running on dev store. I can't find any documentation. 

Is this normal? Or do I need to scrap this app, and register another new app? 

Thanks!