iPhone 5 doesn't let me change my ID

Hello,

When I am in the Preferences:

I am logged in with my current Apple ID.

In the App Store I am logged in with my old Apple ID.

My problem is that I want to use my current ID in the App Store, but I can't change my icloud ID's.

I can't change both of them, the fields of the ID's are light grey and nothing happens when I tap them.....

I have also tried to change them in itunes, when I connected the iPhone to my Mac, but I didn't find any settings...

Thanks in advance for help (sorry for bad english 😉)