6months old baby stop drinking milk


My 6 months old baby completely stop drinking milk. I tried everything but nothing can make him to drink milk. Before I start solid he used to 15oz milk per day after he started solid he completely stopped. Last few nights he had 5oz milk in sleep but last night after he had his dinner at half 6pm he didn’t take his milk at all. I’m so worried frustrated don’t know what to do. he also looks small compare to my older boy in this age. If you know what I mean. Iam adding his milk powder with his food but don’t think it’s enough for his age. Is anyone else babies doing same things. 😥😥😥🤫😥