No Content-Security-Policy meta tag found

Hello, I have read 50% of what’s currently on the internet regarding this issue. My GET requests are fine but my PUT requests don’t write anything into my database. I learn that this issue is caused by how Cordova5 handles security. The steps I took were:

1- installed the cordova-plugin-whitelist
2- added this in config.xml:
<meta http-equiv="Content-Security-Policy" content=" default-src *; style-src * 'unsafe-inline'; script-src * 'unsafe-inline'; media-src *; img-src * data:;" />
4- ionic run android

And I still get the same error!
"No Content-Security-Policy meta tag found. Please add one when using the cordova-plugin-whitelist plugin.", source: file:///android_asset/www/plugins/cordova-plugin-whitelist/whitelist.js (26)

Does anybody have any idea why? I even tried to copy the code to index.html inside of www and even replicated the code but the tag seems to be invisible which is hilarious.