Doubt with the billing mode

I made an app with a form that collects information, the idea is to share the browser link on a social network.
When I do the deployment check it tells me that it is suitable for the FREE plan, but when I implement it, I get an error in My Account, that I have to buy licenses.
Require Sign In = OFF
Online Sync = OFF

How is this?

You can’t deploy an app on a free plan.

Please contact for help with this.

Oh ok, and in prototype mode, what limitations do I have?

You can deploy a free app technically. But in order to stay “under the radar” so to speak you are limited to less than 10 users. Assuming these users utilize the log in features, they are limited to 5 devices per user.

In the case of purely anonymous users, like your collecting of information, each person who is opens the link counts as a user. If your sharing it on a social network, you will quickly exceed the free 10 user limit.

And no matter what, if it is for business purposes, you’re supposed to give them money.