Ethernet not connecting to 2.4g but does connect to 5g

Solution
5G and 2.4G are shortened names of 2 frequencies (5GHz and 2.4GHz) that WIFI (protocol 802.11) uses to make wireless connections. Ethernet (protocol 802.3) uses a physical medium (coax, twisted pair copper, fiber optic, etc) to make connections.

So, with that information I hope you can see that your question does not make sense. You don't use an ethernet cable to connect to 2.4g or 5g.
5G and 2.4G are shortened names of 2 frequencies (5GHz and 2.4GHz) that WIFI (protocol 802.11) uses to make wireless connections. Ethernet (protocol 802.3) uses a physical medium (coax, twisted pair copper, fiber optic, etc) to make connections.

So, with that information I hope you can see that your question does not make sense. You don't use an ethernet cable to connect to 2.4g or 5g.
 
Solution