React-native-auth0 embedded social login not returning refresh token

Here’s a sample response from the call to /authorize using &access_type=offline and expo AuthSession.startAsync(authUrl)

{
    "errorCode": undefined,
    "params":{
         "access_token":"eyXXX...",
         "exp://localhost:19000/--/expo-auth-session": "",
         "expires_in": "7200",
         "token_type": "Bearer",
    },
    "type":"success",
    "url":"exp://localhost:19000/--/expo-auth-session#access_token=eyXXX..."     

}

There is no error when I include access_type=offline as a request parameter, but “params” does not contain the refresh token.