I cant join multiplayer

I cant join!! I was playing pokemon Y and wanted a gengar so badly! I tried joining other servers but it won work!! Everytime I try, It just says this
Screenshot 2022-08-27 214531

Is there another way, I really wanna get a Gengar

Try launching Citra as an administrator. If that doesn’t work, contact the room’s host(s) and tell them to properly port forward their Citra room.