Refused to display  in a frame because an ancestor violates the following Content Security Policy directive: "frame-ancestors 'self'".

How to fix this issue,Due to iframe this error was coming 

Okay, So i am new to apex and visualforce.  I have been working on a project for about a week now. Everything was going good until yesterday when anytime i modified my code and saved the changes my visualforce page would not show the new modifications. It is like it just completely stop responding to anything i was doing.  Has this happened to anyone else? If so how did you correct the issue(s)?