Baby hates skttinf up

My daughter is almost 7 months and not sitting up which is fine. Every baby is different. But I try practicing with her. I sit on the floor and put her between my legs so if she tips she has my legs to bounce her back up.

Whenever I put her in a sitting position to practice she cries and screams the whole time until I put her on her back or belly. She can kind of lay her belly on her legs but she can’t get herself back up to a sitting position so she gets mad.

Is there anything else I can do to  strengthen those muscles that she won’t throw a fit over? Lol