API connection to multiples tiendanube.com's stores

Hi all,

I have a problem trying access the tiendanube.com API, for multiples stores from bubble.is

I build a website with bubble.is to add functionality to multiples stores in tiendanube.com with coupons and this kind of things

I was work in parametriced plugin to connect with tiendanube.com, with a parameter store ID. The access token obtained from each store must by saved into my data to be used on each json request. I be working with OAuth2 User-Agent Flow, the only connection used by tiendanube.

I try to solve that through a new plugin, configure all and works! but the access token are into a json structure unknow by bubble, and i take an error.
I take this access token manually to configure each connection to this store and works, but i don’t understand how to automatize the use of access token with multiples stores and users.

In resume, how can i automatize the token provided for each user/store?