@dr.yanet  Hello, 

Thank you for your valauble feedback.Please locate camera very close to router during set up, ensure the Kasa app is up-to-date 

Here are some suggestion you could give it a try:    

• Change router's DNS to 8.8.8.8/8.8.4.4
• Turn off or lower firewall settings on router & Modem 

• Ensure camera is connected to main router directly not through AP or extenders
• You could try to change a different 2.4Ghz Wi-Fi channel on router and see if that helps 
• Turn off Advanced wireless settings like WiFi optimizing Band steering etc. 
• Turn off AP Isolation/ Client isolation on router. 

May I know the Router model and your network topology?  
e.g. Router Archer C7 (in living room) <wireless> camera in living room) 
When camera not found on Kasa app, connect phone to the home WiFI and see if you could see camera？ Can you check if camera shows up on router's client list, do you have other tp-link device that
Thank you.