Why my taranis x9d plus 2019 can't bound sub protocol

I’m new playing quadcopter. I have taranis x9d plus 2019 and jumper JP 4 in 1. I have downloaded the latest open tx 2.3.7 firmware on my taranis x9d plus. But why i can’t find sub protocols in my External RF menus, just protocol only. But if I don’t use the JP 4 in 1 module and I try to look at the external RF menus there, I find a sub protocol in the multi menu. Anyone please help me. Thank you.