My Son Is Nine Months Old. He Had His Tongue

My son is nine months old. He had his tongue and lip tie revised when he was a month old. Around six months when we started solids, he kept vomiting. He Vomits in purees and any textured food. He always gags first before vomiting. Some days he does very well but other days he vomits two to three times a day and it's a lot. I noticed after he had viral bronchiolitis twice, he has so much mucus stuck in the back of his throat and lots of clear snot in his nose. I have to clean it daily or else he won't be able to eat. Can you please tell me what could this be??? Its really hard seeing him like this.