refresh_token grant not working

Hi,

I'm currently developing a e-commerce solutions using a headless drupal/GatsbyJS(react) setup.

I'm running into problems when trying to use the refresh_token grant. I'm getting the following response:

"error": "invalid_grant",
"error_description": "The provided authorization grant (e.g., authorization code, resource owner credentials) or refresh token is invalid, expired, revoked, does not match the redirection URI used in the authorization request, or was issued to another client.",
"hint": "Check the configuration to see if the grant is enabled.",
"message": "The provided authorization grant (e.g., authorization code, resource owner credentials) or refresh token is invalid, expired, revoked, does not match the redirection URI used in the authorization request, or was issued to another client."

A google search tells me that i should install simple_oauth_extras to enable the refresh grant. But from what I can tell this should already be included in version 8.x-4.4.

Am I missing some configuration or is this a bug? For testing purposes i already gave the role I am using all oauth permissions, but to no effect.