routineer
/ruːtɪˈnɪə/ /rʊˌtiːˈnɪə/noun
A person who acts according to routine; specifically one who adheres to an established or prescribed way of doing something, without recourse to innovation or imagination (frequently depreciative ).
Origin
Late 18th century; earliest use found in The Gentleman's Magazine. From routine + -eer, perhaps originally after French routinier routinier.