Due to a bug related to Magento 2.1.x (Github issue#5596), enabling Cookie Consent causes functionality issues with regards to GTM and GA default Magento tracking. By enabling Cookie Restriction Mode, Magento 2.1.x does not show Google Analytics or GTM tracking, even if the user has accepted cookies.
There are a couple of ways to get this sorted, and allow tracking.
-The first option would be to deactivate cookies.
-The second and most optimal solution involves updating your Magento installation to the latest version. A guide for the update can be found here: How to upgrade Magento 2 to a newer version and install security patches
-The third option involves installing a 3rd party module, found here: Cookie restriction fix
If you choose to install the module, make sure you flush your Magento Cache and delete existing cookies. The specific cookie would be user_allowed_save_cookie, but we recommend removing all of them to avoid any issues.