after I add a wrong UID(59995010079412 maybe) as a Tester in my developer console. my app roles list is gone, related url: https://developers.facebook.com/apps/1295885614720978/roles/roles/?business_id=1234225540923458

then I check browser's devtool, found error blow:

POST https://developers.facebook.com/api/graphql/
response：
{
    "data": {
        "get_app_roles": null
    },
    "errors": [{
        "message": "A server error field_exception occured. Check server logs for details.",
        "severity": "CRITICAL",
        "mids": ["ebfd3692560f6877960c831dfc8ebd18"],
        "code": 1675030,
        "api_error_code": -1,
        "summary": "Query Error",
        "description": "Error performing query.",
        "description_raw": "Error performing query.",
        "is_silent": false,
        "is_transient": false,
        "is_not_critical": false,
        "requires_reauth": false,
        "allow_user_retry": false,
        "debug_info": null,
        "query_path": null,
        "fbtrace_id": "AKAs+vrPjkN",
        "www_request_id": "Asq9mm1JNIH16Gs3ieJNC8R",
        "path": ["get_app_roles"]
    }],
    "extensions": {
        "is_final": true
    }
}