I have completed the game and I have 4 legendaries to catch.
These were Cresselia and the 3 deer trio, which are Terrakion, Cobalion, and Virizion.
I have 3 Pokemon with max EV and I caught Terrakion on a Tuesday. A day later when I went back to the portal to them, which was when Cobalion was meant to be there, nothing happened.
I waited a day later and still, nothing happened. It just keeps saying that "a mysterious ring is floating in the air."
Please help, because I really want to catch Cobalion and Virizion and it isn't working!