The cause is the ESP32 bug. M5Stack Community : M5.BtnA.wasPressed() conflicts with WiFi https://forum.m5stack.com/topic/3262/m5-btna-waspressed-conflicts-with-wifi This is a report of measures for the A button of M5Stack and the B button of M5Stick C to operate without permission. ButtonA on M5Stack does not work properly : May 02, 2021 void setup(){ WiFi.begin(); WiFi.setSleep(false); } or #include <driver/adc.h> void setup(){ adc_power_acquire(); // ADC Power ON : blog : ButtonA on M5Stack does not work properly : May 02, 2021 https://macsbug.wordpress.com/2021/05/02/buttona-on-m5stack-does-not-work-properly/