Making the switch

Hello everyone! I’m attempting to make the switch from breastfeeding to formula feeding with my almost three week old. I’m trying to start with one feeding a day with formula but she spits out the formula and then refuses the bottle. She’s had bottles of breast milk before so I think it’s the actual formula that’s the problem. I’m not sure what to do. I need to make the switch for my own sanity and because I’m heading back to work. Any advice would be greatly appreciated!