There are several ways to block unwanted calls and spam messages. U.S.-based carriers such as Verizon, AT&T, T-Mobile, and Sprint provide support for clients who want to block service-based numbers that disturbed them. Still, the blocking process is time-consuming. Built-in blocking, which is a part of the device's settings allows users to block specific number which then won't be able to call and send messages. Navigate to settings, find "Call blocking" in the Settings menu, and block the number that has been disturbing you. Some manufacturer name the features differently such as "Auto-Reject List", “Block Contact” or "reject calls" etc Android apps on the Play Store offer most of the reliability and flexibility for blocking unwanted calls. They provide additional functionalities such as automatic contact recognition, comparison to other spam numbers in extensive databases, and pattern recognition.