Increase the size of a persistent disk - Fails with unmount error

[Brent]

Hi, I'm trying to increase my disk partition so I can use the extra space I already set in the VM Disk settings (600gb).

However, while following the instructions in this tutorial, "Increase the size of a persistent disk", I received an unexpected error, "Partition /dev/sda2 is being used. You must unmount it before you modify it with Parted." (full console output below)

I expected to be able to continue the tutorial but I'm not sure how to unmount the disk or if I should unmount the disk. It seems like it could corrupt my data. If I take down the server I'm not sure I can bring it back up.

Does anyone know how to get past this part of the tutorial?

--
Last login: Mon Nov 14 02:03:03 2022 from 35.235.242.209
[brentfm@whm ~]$ sudo df -Th
Filesystem Type Size Used Avail Use% Mounted on
devtmpfs devtmpfs 5.8G 0 5.8G 0% /dev
tmpfs tmpfs 5.8G 8.0K 5.8G 1% /dev/shm
tmpfs tmpfs 5.8G 449M 5.4G 8% /run
tmpfs tmpfs 5.8G 0 5.8G 0% /sys/fs/cgroup
/dev/sda2 xfs 300G 221G 80G 74% /
/dev/sda1 vfat 200M 12M 189M 6% /boot/efi
/dev/loop0 ext4 3.9G 8.4M 3.7G 1% /tmp
tmpfs tmpfs 1.2G 0 1.2G 0% /run/user/1002
[brentfm@whm ~]$ sudo lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 600G 0 disk
├─sda1 8:1 0 200M 0 part /boot/efi
└─sda2 8:2 0 299.8G 0 part /
loop0 7:0 0 4G 0 loop /home/virtfs/bigislandfun/var/tmp
[brentfm@whm ~]$ sudo parted /dev/sda
GNU Parted 3.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) resizepart
Partition number? 2
Error: Partition /dev/sda2 is being used. You must unmount it before you modify it with Parted.
(parted)