Error expanding ix-apps pool after increasing disk size

TrueNAS version: 25.10.3 (Community) on Proxmox 9.1.9

I run TrueNAS on Proxmox with a small portion of a physical SSD mounted as a virtual drive in TrueNAS. In TrueNAS I have a pool (“ssd_pool”) spanning just this one virtual drive, which is used for ix-apps and a few manually created datasets. Since this pool was filling up due to a growing ix-apps size, I increased the virtual drive size in Proxmox from 64GB to 128GB, which immediately showed up as the new VDEV size of the ssd_pool. However, the “Usable Capacity” doesn’t automatically update and still shows the previous ~64GB (minus file system overhead, I assume). I’m not allowed to show screenshots, so use your imagination. I tried to “Expand” the pool via the GUI button, but I’m getting this error:

[EFAULT] Command sgdisk -d 1 -n 1:2048:+132874240KiB -t 1:BF01 -u 1:0a370b0e-963d-43cd-ba1e-f3345b124a6b /dev/sdb failed (code 4): Could not create partition 1 from 2048 to 265750527 Could not change partition 1’s type code to BF01! Error encountered; not saving changes.

Is this because the ix-apps data is stored in this pool? What’s the correct way to expand the pool to use the full disk size?