@Dev1607, From your post it sounds like you’re programmatically creating Access API Customers, so I’ve updated the thread to reflect “Access API Support”.
Can you clarify what you mean by add money to their accounts? where are the funds coming from and going to?
If you’re integrating with the Access API, then there’s no need to deal with the refresh token flow since you can use an application access token for all calls in the API.
The dwolla-swagger-php client library doesn’t currently contain support for OAuth, therefore you’ll want to use an external PHP REST client for making requests to the Dwolla API for OAuth related functions. Something like Guzzle, Requests, or cURL would work. There are also a lot of resources on the web that will make working with OAuth easy.