Error login to sonarqube using gitlab credential

Hi, I tried setup the integration with gitlab using document as shown below:

After that I tried to login to sonarqube with gitlab, and it actually prompts this error right after clicking gitlab in the sonarqube login form (without key in the gitlab credential)
Client authentication failed due to unknown client, no client authentication included, or unsupported authentication method.

Btw, I am using sonarqube community edition 8.6. Trying to use gitlab credential in sonarqube during login.

Closing this thread as a duplicate of the more fully-fleshed