@JuanGutierrez: I'm sorry to hear that you're having network connectivity issues with your S21 Ultra. Is the issue occurring everywhere, or in a certain location? Can you try pressing and holding the Volume Down and Side Keys together for around 10 seconds until the phone restarts, as this will address any temporary software issues that might be a contributing factor. Don't worry, this won't affect your personal data or settings. now, head to Settings > Connections > Mobile Networks > Network Mode, and make sure that 5G/4G/3G/2G (auto connect) is enabled, so you can connect to the strongest available signal in your area. If this is already selected, then try a different option to see if you notice an improvement.