Facebook Lead ads help - invalid URI

Good day to everyeone,

Recently i have been trying to connect our facebook lead ads to marketo however during the authorization phase i get this error

I followed the steps listed here Set Up Facebook Lead Ads - Marketo Docs - Product Documentation  but i only made it until step #5 because of this error

My question is.
1. what app should i create to add the whitelist on facebook (since adding the uri to the whitelist on facebook login app doesn;t work)2. what URI should i put in exactly

3. This also happens to google adwords linking so which settings do i need to change as well.

Thank you in advance! Have a greay day!

Best Regards,
Ken