If hbomax/tvsignin isn't working on your device, it could be due to several reasons. First, check your internet connection to ensure it's stable. Ensure your device and the HBO Max app are updated to the latest version. Double-check that you've entered the correct code at hbomax/tvsignin and that your account is active. Browser cache or cookies may interfere; try clearing them or using a different browser. Sometimes, server outages or regional restrictions can also impact functionality. If the issue persists, restart your device and contact HBO Max support for assistance. Following these steps can often resolve the problem efficiently.