Can't delete I/O rack assignments

I have an LR mate that we are setting up as a trainer robot. Under the digital inputs and outputs config screen, I reassigned the I/O range and start numbers. My current setup for DI looks like

I am not using anything above input 20, so I deleted the assignments in ranges 81-88, 101-120, and 121-132. That made it look like

However, once I reboot my previous I/O assignments all come back. It isn't causing me any problems, but it is something I can't explain. Does anyone have a clue why the I/O mysteriously comes back after rebooting?

That was exactly it! I find it kind of weird that there is an auto assignment considering how differently the robots end up being configured.

Thanks so much for your guidance. I greatly appreciate it.