Hello. The baby constantly sits on all fours. He crawls not very activ…

Hello. The baby constantly sits on all fours. He crawls not very actively - more like a crawling motion and only touches things with his hands and moves by jerks on all fours, his back is still weak and he sits leaning against the handles. I don't know what to do, should I put him down, because it puts strain on his spine? But he constantly does this and gets nervous if I put him down... how did you handle such situations?