query to Find keys having more than one values in the list Mongodb

Question

I have data in MongoDB like the below

test{ 
[{"key":"469","values":["BALTIMORE","BALTIMORE CITY"]}],
[{"key":"503","values":["BALTIMORE"]}],
[{"key":"505","values":["FAIRFAX"]}],
[{"key":"517","values":["COLUMBIA","BELAIR","BELAIR"]}],
[{"key":"534","values":["BETHEL","BETHEL"]}],
[{"key":"471","values":["HAGGERS","HAGGERS"]}],
[{"key":"587","values":["SAN FRANCISCO","SAN FRANCISCO"]}],
[{"key":"551","values":["DALLAS"]}]};

i would like to get the keys having more than one values. like

[{"key":"469","values":["BALTIMORE","BALTIMORE CITY"]}],
[{"key":"517","values":["COLUMBIA","BELAIR","BELAIR"]}],
[{"key":"534","values":["BETHEL","BETHEL"]}],
[{"key":"471","values":["HAGGERS","HAGGERS"]}],
[{"key":"587","values":["SAN FRANCISCO","SAN FRANCISCO"]}],

Any help appreciated.