Some of my Runners started out laying soft eggs, so it could be a simple start-up issue. Just give them layer food, some crushed oyster shell on the side, maybe add a little Ca citrate once a week (maybe 100 mg each time), and sit tight for a week or two.
If she shows signs of being uncomfortable, does a lot of tail-pumping, then it could be an oviduct problem, and a vet may be a good idea.
If she shows signs of being uncomfortable, does a lot of tail-pumping, then it could be an oviduct problem, and a vet may be a good idea.