Lots of good replies already, and it is a really common question if you search around.
Yeah, it isn’t surprising! The best advice I got was to stick it out and do my best about keeping good habits. Clean living stuff like watching caffeine in the afternoon, try to get to bed and get up at a certain time each day (even when it sucks). “Sleep hygiene.”
Little by little it gets better. Now I naturally crash at 11pm usually, and always wake up ready before my alarm! Took weeks or maybe months before it leveled out though.