APC 1200 via USB not working

I have a ReadyNAS Pro 4 (4.2.31) connected to an APC XS 1200 via USB with no issues.

I moved that USB to this my other ReadyNAS 426 (6.10.4) and I get the following errors (I removed the serial number):

Dec 30, 2020 02:27:57 PM System: New USB UPS detected. Manufacturer: , Model: , Serial: <xxxx>.

Dec 30, 2020 02:28:00 PM System: Error communicating with UPS 'UPS' ().
Dec 30, 2020 02:28:03 PM System: Cannot communicate with UPS UPS ().

I'm new to version 6.x so I have nothing to compare against.