Call Sign with no SSID for command

Call Sign with no SSID for command

VY1XY 24 Apr 2020 02:57

I have to use the chat message system to transmit commands to a remote station. But the station will not accept a call sign with the SSID attached. I have done it before but I forget how I did it using the chat message system. If I use the chat message now it will automatically add the SSID of my station.