Came back with some updates.
Some people gave screenshots and vids(both here and in BG3 subreddit) and said it could be a mod conflicting with the game resulting in it getting bugged.
The mods i use are tashas hair mods and armor/weaps mods.
Removed the mods, deleted the whole campaign.
Started a new one, same dialogues, nothing fixed.
Last resort i had before uninstalling and re-installing was verifying the integrity of game files.
Did it, started a game and finally the Githyanki options where there.
Deleted that campaign again, re-added the mods , went back to start anew and everything seems to be fine. Still dont know what the conflict was , but its working as it was intended now.