I'm on an Android S20.I'm connected to wifi but it says without internet on my phone. My iphone next to the android phone has connection My Galaxy S6 tab next to the phone and next to the deco P9 also

Hi, Recently I have a problem in my tp link deco app, whenever I open the app it says my phone or tablet is offline. I am connected to my Wi-fi network, and can use it.. so that isn"t the problem. I h