• Which web browser are you using?
• What’s the device?
• How long is it taking to change the modes? It should take less than 2 seconds
• What do you see in your Arduino IDE serial monitor when you change modes? Does it take too long to print the serial monitor the different debugging information?

Google chrome.
Sometimes it takes minutes to load.
Power bank is used to power esp32 

• Are you using Google Chrome in what device? Android smartphone or laptop?
• As I said, it should take less than 2… 5 seconds to load the page, so unfortunately that’s definitely not normal behavior.
• What do you see in your Arduino IDE serial monitor when you change modes? Does it take too long to print the serial monitor the different debugging information? Can you post the Arduino IDE serial monitor log between changing modes?

In laptop
When i power esp32 via powerbank nothing appears on serial monitor

Thanks for the info! Some old Android smartphones might be too outdated and slow loading web page that’s why I was asking.

For testing purposes, can you connect the ESP32 temporarily to your computer and change modes?

Does it take too long to print the serial monitor the different debugging information? Can you post the full Arduino IDE serial monitor log between changing modes?

Thanks for your cooperation!

https://imgur.com/4sVFiN5

sometimes i have to click two times also to on/off gpio

Hello, I think your web browser is leaving the connection open and that’s why you can’t change the settings. I think I was able to find the solution.

Can you follow this solution and add the timeout code to your ESP32 Multisensor web server code?

[SOLVED] ESP32/ESP8266 Web Server Drops Connection/Crashes

Let me know your results. Thanks for your patience!

Still not working. Should i connect  3.3V gnd to 5Vgnd
What is the minimum Internet speed required? 

If the relay operates at 5V, you should use 5V. But you can send a 3.3V signal to control the on and off state with your ESP…

It’s a local server, so I don’t think the Internet speed will make any difference (probably just a old browser or slow device might cause that problem).

Unfortunately I can’t replicate that error on my end…

Unit1 – ESP32 Wi-Fi Multisensor; Unit 7: Accessing the ESP32 Web Server From Anywhere;

I pasted this code and it improved. Should i increase timout delay to 5 sec

It still a bit slower that it should, I’m not sure what else I can say right now. Just as last debugging test, I would try with a different device or web browser to see if it decreases the web page load speed.
Thanks for your patience!