I updated my iPhone to iOS 12 and noticed first that all my contacts no longer syncing from my Gmail account. I also cannot access the App Store.
In Settings I have tried multiple times to sign in with my Apple ID but it just doesn't work. I have restarted my device multiple times. There isn't an option under Contacts in the settings to set the default. I've tried over wifi and over cellular, nothing is working.
What else can I do to try resolving this?