2nd monitor is mirroring the first external monitor

Solution 1:

I was using the Hyperdrive Pro Docking Station, and apparently its sharing the signal for its HDMI and DP port. I had to buy an adaptar (USB-C to HDMI) to attach the second monitor to the hub, and this solved the issue.

Solution 2:

The mac support: https://support.apple.com/guide/mac-help/use-multiple-displays-mchl7c7ebe08/mac

It says

For Mac computers with Thunderbolt 3 (USB-C): You can connect a single display to each port. If you connect multiple Thunderbolt devices to each other, the Thunderbolt 3 display must be the last device in the chain. If your Thunderbolt 3 display has USB ports, those can be used for data and power.

So, I am connecting it to another USB-C port of mac. I am not sure if this is the best way, but Mac is limited to support this..