Reply to 3 yr old starting to hit

Most likely she picked it up from other kids at daycare. My son stays home with me and is starting to hit too... we have been around a lot of other toddlers his age lately because of the classes we are taking. The kids have hit him and now after 6 months in the classes he is starting to hit too. We don’t hit at home either. Don’t have any great tips as we are in the same situation. I try holding his hands together so he can’t hit until he calms down. I’ll say “it’s ok to be angry but it’s not ok to hit.” No progress so far 😕