Problem with mounting my External Hard Drive

I accidentally unplugged my Toshiba Canvio Advance 4TB Portable External Hard Drive USB 3.0 without unouting it.

I have a macbook Pro (13-inch, 2019, Two Thunderbolt 3 ports) with Big Sur 11.3.1

Now it shows up in disk utility. It wont let me verify, repair, or mount it from the disk utility app.

When i try to unmount it from terminal here is what happens:

leahmurdoch@leahs-MacBook-Pro ~ % diskutil unmount /dev/disk1s2

Volume Macintosh HD - Data on disk1s2 failed to unmount: dissented by PID 1 (/sbin/launchd)

Dissenter parent PPID 0 (kernel_task)

Here is what happens when I try to mount it from terminal:

leahmurdoch@leahs-MacBook-Pro ~ % diskutil mount /dev/disk1s2

Volume Macintosh HD - Data on /dev/disk1s2 mounted

And here is what happens when I tried the third option of quickly unmounting/mounting it from terminal:

leahmurdoch@leahs-MacBook-Pro ~ % diskutil unmount /dev/disk1s2;diskutil mount /dev/disk1s2;echo "Remounted Volume"

Volume Macintosh HD - Data on disk1s2 failed to unmount: dissented by PID 1 (/sbin/launchd)

Dissenter parent PPID 0 (kernel_task)

Volume Macintosh HD - Data on /dev/disk1s2 mounted

Remounted Volume

These are things I tried from here:

https://osxdaily.com/2013/05/13/mount-unmount-drives-from-the-command-line-in-mac-os-x/

None of these worked. I have tried using a new cable connector and restarting my computer.

Im at a loss. Can anyone please help me?