Vaal Temple - Skill Gem Disappears after Disconnect

During a Vaal Temple run, I encountered a workbench that allowed me to upgrade a skill gem by adding an additional support gem socket. I used the workbench to upgrade one of my skill gems, and the upgrade initially worked as expected.

Later during the same Temple run, I was disconnected from the game. Upon reconnecting, the entire Temple run had ended, and I was unable to continue or complete it.

After further inspection, I noticed that several items I had picked up during the run had disappeared. Additionally, the upgraded skill gem was completely missing from my inventory.