After that error occurred on the master node, we tried to update Fog to version 1.5.10.2518, but it would NOT let us update the schema; the installation got stuck and didn’t complete.

Virtual machine running Ubuntu 26.04 LTS with FOG 1.5.2518. The master node is another non-virtual machine running Ubuntu 20 LTS. Both machines are on the same subnet.
The FOG web interface cannot access the master node.
I used to have a virtual machine running Ubuntu 20 LTS and FOG 1.5.9, also with the master node on the other machine, on the same subnet. Everything was working fine until one day when the FOG web interface wouldn’t let me run tasks, telling me I had to update to version 1.5.10, which forced me to update it. At that time, the stable version was 1.5.10.2482; I installed it and, since then, I have been unable to access the Master Node, which is where we store all the images.
I’ve been trying to sort this out for days and can’t seem to find a solution.

How can this be resolved?