Pages failed to create new project

Developers Cloudflare Pages
6

Hi I have created a page project previously. I want to create a new one but what I get is

An unknown error occurred (Code: 8000000)

I tried to use web console, the following request returns 500

https://dash.cloudflare.com/api/v4/accounts/{account id}/pages/connections/github

{
    "result": null,
    "success": false,
    "errors": [
        {
            "code": 8000000,
            "message": "An unknown error occurred"
        }
    ],
    "messages": []
}

Any idea?