Aeon Multisensor 5 LED stuck on after changing flat batteries

This is the third Aeon Multisensor 5 that has done this. If I fail to change the batteries before they go 100% flat, when I do change them, the sensor comes back online just fine, except the Red LED remains lit and never goes off. Drains the batteries in a matter of hours.
I’ve tried factory resetting the device. To no avail. I’ve tried removing and re-pairing the device. Same outcome. Red light remains on.
I’ve also tried to flash the device using Aeon’s flashing software for both version 17 and 18. Neither flashing utility can detect the device (also synonymous with my other devices).

Has anyone encountered this and if so, how did you resolve to get the device to return to normal operation?

Thanks in advance