Disk resize failure

I have two VM’s that were instantiated at the same time. Today I attempted to resize the disk from 10GB to 25GB. The disk on the first vm was successfully resized. However resizing the second VM fails withe the log showing:

Command execution failed (exit code: 1): /var/lib/one/remotes/tm/ssh/resize /var/lib/one//datastores/129/199/disk.1 26624 199 111
resize: Command “qemu-img resize /var/lib/one/datastores/129/199/disk.1 26624M” failed: qemu-img: Can’t resize an image which has snapshots
qemu-img: This image does not support resize
Error resizing image /var/lib/one/datastores/129/199/disk.1
Error executing image transfer script: Error resizing image /var/lib/one/datastores/129/199/disk.1
VM disk resize operation completed

I know from past experience I cannot resize a disk that has a snapshot taken. But I don’t recall ever taking a disk snapshot of this VM’s disk. And no snapshots appear under the Storage tab.

Any idea how to solve or what to look for next? Or at least verify if a snapshot was taken?