The song “1 Step Forward, 3 Steps Back” credited Taylor after using an interpolation of her track “New Year’s Day.” Then, after the release of the album, fans noticed Taylor was retroactively credited for another song along with Jack Antonoff, St. Vincent, and then, eventually, Paramore for another track.
Source: https://www.buzzfeed.com/mychalthompson/olivia-rodrigo-taylor-swift-feud-response