dual boot – Ubuntu does not detect 2nd HDD (Acer Aspire 3)

Installing Ubuntu 20.04 (U20). Laptop: Acer Aspire 3, model # A315-56. Laptop comes with 2 disks:

  1. Disk1: 256GB SSD
  2. Disk2: 1TB HDD

Laptop has Win10 on Disk1. Disk2 is just empty.

First attempt to install U20 on laptop was not successful due to:

After following the steps there, U20 is able to detect Disk1/SSD and I was able to install Ubuntu on it.

However, the second drive i.e. Disk2, remains hidden to Ubuntu. This disk is not found by lsblk, fdisk, lshw… nothing.

But logging out (from U20) and logging in to Win10, it is there, appearing as a huge 1TB empty hard disk.

Is there a step I missed to get U20 to detect this second HDD?