If your neighbor is using your WiFi, the fundamental problem is that they have your password. Change your router password to a strong password and make sure you use WPA2 authentication. Make sure you perform the router change from a wired connection and disable WAN side administrative access. Spoofing your MAC address would be a poor choice for them ...


You mention that in comments that you are a novice and it appears you do not understand wireless in any great deal. You also don't provide a lot of information so your "problem" is very vague. When a device associates to a wireless network, it goes through a number of steps. Among these steps there is an "open authentication" which normally is simply a two ...


This is probably due to a server issue at Syniverse which is being reported today by the media. See https://arstechnica.com/information-technology/2019/11/why-168149-valentines-day-text-messages-arrived-in-november/.

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