Add new Firewall Mangle using API

RouterOS Scripting
1

Hello guys!

i’m using the API in C# to add and remove Firewall Mangle.

i can print and remove mangles but i can not add new one!

i can add mangle in terminal and ssh:

 ip firewall mangle add chain=prerouting src-address=192.168.25.25 comment=username new-connection-mark=conn1 disabled=no

but it does not work in API:

        private void addMangle(MikrotikAPI mikrotik)
        {
            mikrotik.Send("/ip/firewall/mangle/add", false);
            mikrotik.Send("=chain=prerouting", false);
            mikrotik.Send("=src-address=192.168.25.25", false);
            mikrotik.Send("=action=mark-packet", false);
            mikrotik.Send("=new-connection-mark=conn1", false);
            mikrotik.Send("=comment=username", false);
            mikrotik.Send("=disabled=false", true);//false or no

            foreach (var res in mikrotik.Read())
                Debug.WriteLine(res);
        }

in result i got:

!trap=message=no such command prefix

RouterOS: V3.2 and 6.13

any suggestions?