Unable to Verify GitHub for Reward Pool Participation

When trying to join the ArcBlock 202509 Github Reward Pool event, I clicked the Verify button to connect my GitHub account. However, the system rejected the request with the following error:

Request failed with status code 400

This feels inconsistent, since my GitHub account is already connected to my profile, but the event verification still fails. As a result, I cannot join the event.

Could this be a server/API issue that isn’t handling the request correctly, or is it an expected limitation for certain users?