Advice on behavior issue

My daughter is 10 1/2 months and recently has started hitting me in the face. I sternly tell her “no” and she just thinks it’s the funniest thing. I don’t react, but again say no. If she continues I say “we don’t do that” very strongly, if I continues I repeat the saying and put her in a baby

Play yard we have for a minute or two. She cries a lot, but I make her stay in there. It isn’t helping, she’s still doing it - any advice as to how to get her to stop? Thank you.