Girls!!! Such a question!!! Son is 2 months old, he sleeps only in arm…

Girls!!! Such a question!!! Son is 2 months old, he sleeps only in arms during the day (I put him down and he opens his eyes immediately) and at night he sleeps by himself (right next to me, but alone) What's so funny I can't understand why I can't put him to sleep during the day! Maybe someone had this problem, how did they solve it?