Ubuntu no internet when connected to TP-link router?

Question

WiFi

Good afternoon!
The problem is this:
There is a laptop on Ubuntu 20.04 OS, when I try to connect to the Tp-Link router, there is no Internet, although it connects to the router.
If you register DNS 8.8.8.8, 8.8.4.4, the Internet only works for a couple of seconds and then turns off.
To the Xiaomi Mi-WIFI router with 2.4 GHz and 5 GHz purity, everything works OK, when distributing the Internet from the iPhone 11 pro, everything is OK, there is a connection and there is Internet.
I tried to connect to another TP-Link router - the same there is no Internet.
What information do I need to send in order to be able to help me?
Thank you very much

Answer 1

configure the router correctly so that it distributes addresses via dhcp
Check the connection settings on the client side.