Esp32 issue

[MadridR]

I have esp32 connected to my customized 7 segment and power supply 12 module connected to lm2596 to provide 3.3V power to esp32 , 5 CAs pins of 7seg connected to gpios esp32 and cathodes of 7 segment also connected to gpios esp32 and multiplex display the problem is when esp32 is about to connect to wifi modem the display is blank and has flickering and every few seconds in wifi connection blank happens

 

[Galgso]

Sounds like the surge in current that occurs when the ESP32's wireless circuitry is activated is loading down your supply and causing the voltage to drop. How much current can your supply output and what's the current rating on your lm2596 buck converter board?