[krystal]

really soft what can i do

[PaulineM]

A little bit more info might help.  Are the shells really thin or is there no shell just a membrane? 
What age is the bird?

[joyfull]

How old are your birds?
Are they all laying soft shells?
What do you feed them?

First of all omit all treats for the next few weeks - just have layers pellets/mash and grit and oyster shell available at all times during the day. If possible restrict their movements to a run rather than free ranging although in my case this isn't possible so may not be in yours either.

Keep a close eye on them as laying soft shells is hard for the hen as she has nothing for her muscles to push along very easily and also they could rupture inside and lead to complications.

[Casey76]

Remember, that the odd soft shelled/no shelled egg is not an issue, only when they become persistent