When you want to improve your Facebook ad tracking with Conversion API
To set up the access token, you need the right permissions. Make sure that you or your client has full control permission for the account linked to the pixel. This is necessary to create the access token.
How to check if you have the right permission to the Pixel in Business Settings
Do I need to be the Business Admin to use the app?
To use the Facebook pixel on your website, you only need to give us the Pixel ID. This allows the pixel to work on the browser side.
If you want to use the Conversion API (which sends data from the server), you'll need to provide an access token too. This token lets Facebook know we're allowed to send server events to your Pixels.