Unable to refresh oauth 2 token using Qonto integration

[RJiraya]

Bug Description

We are note able to refresh token with Qonto integration because the option send credentials in body is not applied for the refresh token method.

To Reproduce

1. Create an oauth application that used credentials in body (I'm using Qonto API)
2. Configure the OAuth 2 credentials
3. Connect to the service
4. Wait token expires
5. Retry the flow
6. You will get an error like Client authentication failed (e.g., unknown client, no client authentication included, or unsupported authentication method).

Expected behavior

The token should be refreshed passing the credentials in the body

Operating System

Docker 24.0.7

n8n Version

1.30.0

Node.js Version

18.19.1

Database

SQLite (default)

Execution mode

main (default)

[Joffcom]

Hey @RJiraya,

Is this a generic oauth2 credntial you are using and did you already try setting it to use body instead of headers for auth?