`invalid_grant` on refresh token

[Juliotati]

Hi, I've been facing an issue when logging in with the same credentials on different devices on mobile. I'm receiving invalid token error message after my token expires, but when I attempt to refresh the user session by doing a post request I get invalid_grant.

Is it possible that different devices are receiving the same refreshToken which causes the issue of invalid_grant as the quoted definition says:

The "invalid_grant" error usually means you tried to use the same authorisation code to get more than one developer token.

Request body:

{
 'grant_type': 'refresh_token',
 'client_id': CLIENT_ID,
 'refresh_token': REFRESH_TOKEN
}

I would be delighted if someone can point out if I'm missing something on the request body or something else.

Thanks