iFrame Question

Hello,

I am trying to use an app that states the following, “If your Bubble app is displaying blank, please contact support at bubble and request for your app to be allowed to be iframed.”

I have went to Settings–>General–> and selected the "Allow to render the app in an frame/iFrame (X-Frame_Options) to “Allow all iframes”.

I am still new to this so, any help would be appreciated.