BIOS updated failing

Optiplex Micro Plus 7010 with available BIOS update per Dell Command. Have tried to install 3 times with message of "1 update(s) failed" each time. No activity on PC during update process. Did not power on/off or unplug any peripherals per instructions. Per the log, the update was downloaded and verified. The Failed update log entry includes Exit Code "-1", though I'm not sure if that's meaningful. The rest of this log entry is just version and machine info. It seems to have attempted 3 times before terminating the update process.