Stitchwort

Been doing some looking for this plant, we've seen it in grassy areas like Hastings Country Park (this photo) and in the Filsham Reed Bed location on the hills in the grasses along the paths.
Most of the flowers I've looked at this most resembles Sandwort of some variety, however most sandwort flowers are either singular lobed or have only a slight hint of being bilobal.

Close up of flower