Omen disabled in Valorant due to a game-breaking bug
When Valorant Patch 1.07 dropped, Omen had two game breaking exploits and for which there were no counters.
One of these two allowed Omen to teleport through the spawn barriers before the start of a round on Bind A site. The other allowed Omen to become invincible if players used his ultimate at the perfect time somewhere around the end of a round. If they managed to pull it off, Omen could no longer be damaged for the entire game.
Riot has temporarily disabled Omen
Needless to say, this is something that had to be fixed as soon as it came out. In that regard, Riot has temporarily disabled players from choosing the agent while they work on him.
Earlier this week players began to report a bug where Omen would become invincible after using his ultimate ability at the end of the round and having it canceled. Many players were claiming to have been deranked due to losing games against opponents utilizing this bug.
Teleporting through the spawn barriers was an issue players had reported before the other bug. This allows Omen to glitch past the spawn barrier on the map Bind and enables him to enter the enemy’s side before the barriers were lifted.
What Riot had attributed to be a map bug for Omen teleporting past the spawn barriers, is actually an issue with Omen and hence they are disabling Omen until any 'real fix' is found.