5 months rough sleep

Our LO is waking up every 2-3 hours during the night. She used to sleep through the night maybe waking a couple times just wanting her pacifier back in. But now we have to pick her up and rock her until she falls back to sleep. Even if then, when we put her down, she wakes up. She is not hungry during these times. She starts to cry bc she's frustrated she keeps waking up once we get her to sleep. I've seen a couple other posts about this with others replying that it is happening with their LO too. Does anyone have some advice?? It will take an hour of rocking, putting down, wakes, rocking, putting down, wakes, etc. until she stays asleep (for about 2 hours then it happens again). We want to help her sleep better, and of course we want to get back to sleep too.

Help! First time mom.