Unable to load Okta URL in an Rad window. getting X-FRAME-OPTIONS = SAME ORIGIN ERROR

Iam developing Net documents SSO with OKTA. After entering the details, I cant able to redirect to the original page, getting X-FRAME-OPTIONS error.

Iam loading SSO page in Rad window. It is treating as IFRAME. If I change settings in customization(IFRAME EMBEDDING), I can able to load the page.