i can not change themes of my forms.

I need change old forms themes. But i don't change. I'm changing, saving and closing. 

But not save.

Hello,

I've cloned and tried one of your form named "CV Form Template" and I've managed to change its theme. Please find the screenshots below to see:

Unfortunately, I could not reproduce the issue you had. Could you please give us more detail about your problem?

Thanks.