I encountered a very weird problem with my ESP8266 development device with the MAC address. I was doing this work on an AT&T network. When I launch the UI, mos was telling me the MAC Address was A220.... , but when the network was getting the MAC Address on my HTTP or MQTT requests, the device was sending A020.... Only the second digit was off. I am not misreading the MAC address from mos. Everything else was the same. I don't know if this is a device error, a mos error, or a AT&T error. Is there anyway to confirm or test what the problem might be, or what the real MAC address is? I tried with a ESP32 development board and did not have the same problem.