Why SignalR stateChanged callback function hitting multiple times

Question

We have a signalR hub and JavaScript client. when state is changes from connected to disconnected or any state,then callback function hits more time,according to number of previous connections, here is my code:

        var promise = new Promise<SignalR.ConnectionStates>((resolve, reject) => {
            $.connection.hub.url =BASE_URL!;
            $.connection.hub.logging = process.env.REACT_APP_CONSOLE_LOGS == "true";
            $.connection.hub
                .start({
                    transport: ["webSockets", "longPolling"],
                    jsonp: true,
                    xdomain: true,
                    waitForPageLoad: false,
                } as any)
                .done(() => {                      
                    resolve($.connection.connectionState);
                    this.SubscribeBreakAlerts();
                })
                .fail(() => reject("Could not connect"));
        });

        await promise;

        $.connection.hub.stateChanged((e) => this.stateChanged(e));
        $.connection.hub.connectionSlow(() => this.connectionSlow());

i need to find the solution of this issue