dedicated host not visable CS.GO

hello

i have recently made dedicated sever for cs.go

but my server is not being shown in internet option

port mapping is 27015-27055 TCP/UDP for external port and internal

i also have option port trigger but i dont know that i have to do any thing there or not

but if i give my ip to friends then they can join.. but the problem is that only few friends can join not ALL ..

limit is 16 so its not limit problem

so any help pleasee