Ever since new ipad update it won't let me use the gold bars i've purchased

Hey Kayla- Welcome to King Care! I am really sorry that you are experiencing some problems making purchases. Here are a few steps which fix the vast majority of issues:   

Open the game on your Apple Device.

Try to make a purchase.

If you receive the error message then please close the pop-up screen.

Select the Menu option in the bottom left hand corner and sign out of Facebook.

Double click your home button and swipe all the open apps off the screen.

Now turn your device off and leave it for two minutes in order to clear the cache.

Finally, please reconnect to Facebook and then try to make a purchase again. 

 If these steps don't work could you kindly come back to me with the following information:

 Game app version: Go to App Store > Updates > find the game > Here you will see the app version

The make, model and operating system of your device: Go to Settings > General > About > Make a note of the "model" and the "version"

Thanks a lot, have a sweet day! :-)