Foreman 3.1 monitoring plugin problems

Foreman monitoring plugin does not update icinga statuses anymore on hosts, this used to work until version 3.0.1.
Since i’ve upgraded to foreman 3.1, the proxy part still works as expected, but the foreman server logs this :
Started POST “/api/monitoring_results”
ActionController::RoutingError (No route matches [POST] “/api/monitoring_results”)