Resolving issues with iCloud 2FA notifications involves a multi-faceted approach, starting with self-troubleshooting steps and potentially escalating to contacting Apple Support. Initial steps include verifying notification settings, contact information, device trust, software updates, date & time settings, network connectivity, spam/junk folders, and iCloud storage. Apple Support documentation provides guidance on generating codes and managing trusted devices. External factors such as IP address blocks can also interfere with delivery. Apple Support response times vary widely, influenced by issue complexity, workload, time of day, and support channel. Seeking help from community resources like mailop is also suggested when direct solutions are elusive.