Milk

My LO has been spitting up his formula (Nan Optipro) a few times. We did mixed feeding last week and umokay naman sya sa Nan cause wala namang pagsusuka na nangyari. Lately she has been spitting up multiple times pero okay naman ang poops nia. May same case ba as mine? Anong formula ginamit nio mga mommy? Would milk like Nan sensitive or gentle ease would help my LO? Thanks po sa sasagot.