Problems getting ubuntu to use entire disk

[Armuino]

Tried to get help on ubuntu's stack exchange but was told since it involves a proxmox host that it is off topic. The rest is just a copy paste from there.


This is my second install of Ubuntu 20.04 on a Proxmox host, where I have provided 1000GB space and during install Ubuntu only used 200GB of space leaving the rest unallocated. I followed the default LVM disk partition program under the assumption that the use full disk option would actually use the entire disk space for Ubuntu.
I need help getting Ubuntu to use the rest of the unallocated space.
Using

lvextend -l +100%FREE /dev/mapper/ubuntu--vg-ubuntu--lv

does not work, claiming new size matches existing size.
fdisk -l

Disk /dev/loop0: 55.46 MiB, 58142720 bytes, 113560 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop1: 67.58 MiB, 70848512 bytes, 138376 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop2: 31.9 MiB, 32600064 bytes, 63672 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop3: 69.9 MiB, 73277440 bytes, 143120 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop4: 55.39 MiB, 58073088 bytes, 113424 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/loop5: 32.9 MiB, 33644544 bytes, 65712 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/sda: 1000 GiB, 1073741824000 bytes, 2097152000 sectors
Disk model: QEMU HARDDISK
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: D23475A7-B19E-4243-9F05-59E4DBB1A3C7

Device       Start        End    Sectors  Size Type
/dev/sda1     2048       4095       2048    1M BIOS boot
/dev/sda2     4096    2101247    2097152    1G Linux filesystem
/dev/sda3  2101248 2097149951 2095048704  999G Linux filesystem


Disk /dev/mapper/ubuntu--vg-ubuntu--lv: 998.102 GiB, 1072663887872 bytes, 209504                                                                         6656 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

df -h

Filesystem Size Used Avail Use% Mounted on
udev                               1.9G     0  1.9G   0% /dev
tmpfs                              394M 1008K  393M   1% /run
/dev/mapper/ubuntu--vg-ubuntu--lv  196G   37G  150G  20% /
tmpfs                              2.0G     0  2.0G   0% /dev/shm
tmpfs                              5.0M     0  5.0M   0% /run/lock
tmpfs                              2.0G     0  2.0G   0% /sys/fs/cgroup
/dev/sda2                          976M  105M  805M  12% /boot
/dev/loop1                          68M   68M     0 100% /snap/lxd/20326
/dev/loop2                          32M   32M     0 100% /snap/snapd/10707
/dev/loop0                          56M   56M     0 100% /snap/core18/1997
/dev/loop4                          56M   56M     0 100% /snap/core18/1944
/dev/loop5                          33M   33M     0 100% /snap/snapd/11841
/dev/loop3                          70M   70M     0 100% /snap/lxd/19188
tmpfs                              394M     0  394M   0% /run/user/1000

 

[Dunuin]

Proxmox shouldn't be the problem here.

What is lvs and vgs returning?
Did you tried to extend the VG before extending the LV (vgextend)?