Refused to display site in Iframe because X-Frame-Options set to sameorigin

I am having a wordpress site hosted App service and trying to load in and iframe. But i am getting X-Frame options issue. I added headers plugin in wordpress and added X-frame-options heaer with value as *. But still getting the same error and some how App service is blocking us to load. Need to add this header in app service. So i want to know how to add this header in app service

Expecting wordpress site to load in iframe