😩😩😩 need advice don’t know what to do

So with my 7 month old daughter- when she is tired and needs a nap I take her to her nursery.

I turn on the night light and the sound machine and rock her in the chair. When she falls asleep I gently put her in the crib but she ALWAYS WAKES UP and screams and cries! She is clearly tired and needs to take a nap. How long should I let her cry in the crib alone to soothe herself? Any other tips?