Bumbo seat

My baby is 5 months old and sits up with support. Sometimes she gets really agitated laying down and will only calm down if she’s sitting up, which she can’t do on her own yet. Obviously we can’t constantly hold her in that position all the time so we got a Bumbo seat (I know some people say it’s not good for them or whatever, but we need something small that’ll support her without taking up much space.). She seems to enjoy it. But the issue is, she always manages to turn her body just enough that her leg is in a funny position, almost pulling it inside the seat, and I have to keep readjusting her so that it doesn’t cut off circulation.

Is there any way I can fix it so that she can’t shift her body like that?

Any advice on how to make this better would be much appreciated.