TCP and UDP problem

hey,guys

I'm using photon pun in a card game, when I create a room, I have to press home button on mobile and invite my friends by other apps, like wechat or something. When I use UDP protocel to connect to my own photonServer, it works fine, but when I switch to TCP, I always get kicked from my room (mybe the connection was lost, I don't konw),
I want to try use TCP to Connect to my server, so please tell how to solve the problem ,not tell me to use UDP, Thanks