I have attached a picture of the relay/switch in question which is a Otis A6164BP type. Should this relay be staying made up with no power applied to it and not wired? It feels like it magnetically being kept closed/energized once pressed in by hand.
Core should have a groove around the top indicating a hardened core. Also on a set-reset relay, there is a small kickoff spring at the top edge of the armature.