I'm at Bus Stop 66351 (Serangoon Stn Exit B) in Singapore https://t.co/c3aFoYnXi3
<a href="http://foursquare.com" rel="nofollow">Foursquare</a>
North-East Region
[{'url': 'https://t.co/c3aFoYnXi3', 'expanded_url': 'https://www.swarmapp.com/c/eFvpFCQRGcb', 'display_url': 'swarmapp.com/c/eFvpFCQRGcb', 'indices': [58, 81]}]
SERANGOON CENTRAL
["i'm", 'bus', 'stop', '66351', 'serangoon', 'stn', 'exit', 'b', 'singapore', 'https://t.co/c3afoynxi3']
[]
stop exit
bus stop 66351 serangoon stn exit b singapore
  [
    {"relatedness": True, "type": "facility", "explanation": "bus stop is a facility that requires maintenance"}
    ]


    Does the post relate to a maintenance report feedback to public flat house (e.g., a broken facility, an inconvenience, block number or street, requst fixing, etc.)?

The Twitter post "bus stop 66351 serangoon stn exit b singapore" relates to a maintenance report feedback for a facility, specifically a bus stop. Therefore, the answer is:

{"relatedness": True, "type": "facility", "explanation": "bus stop is a facility that requires maintenance"}