Here are a few things to try if a baby is refusing to drink formula.
1. Freeze breastmilk and reheat it for a bottle.
2. Try a bigger nipple in a bottle to make it easier to suck.
3. Switch formulas.
4. See a lactation consultant or Pediatrician.
5. Burp the baby, change its diaper, distract them and then try and give them the bottle with formula.