Because I had only 5 portals and I don’t have more 
Maybe your game just lagged. Maybe try entering the portal again?
Have doing that and it still not working!
You could take a screenshot for them to understand and solve the problem quicker
Hmmm, I think I have experienced this before.
Make sure to open the portal when setting it up, then make sure that the portal is receiving the wiring connection from its trigger.