Baby waking up for multiple hours in the night

My girl turned 6 months on 11/30 and the past week she’s doing this new thing where she wakes up anytime after midnight and she’s up for 1-3 hours. She isn’t necessarily crying - it’s more like fussing, talking to herself, yelling etc. she doesn’t want to eat, doesn’t want to be cuddled, and if we ignore her she just yells louder.

Before this she would wake up once or twice in the night but would just need a quick feed or a few pats on the back and she would go right back down.

Has anyone else’s little one done this and please tell me it’s a quick phase 😩 we are prettyyyyy sleep deprived