Bitdefender Antivirus for Mac says Devices limit reached despite not reaching limit
Bitdefender Antivirus for Mac is reporting that 'Devices limit reached' on my 5th device (out of 5), that I've just installed the product on. Screen shot attached. In my device panel though, there is only 5 devices (which includes the just added 5th device), so I should be able to use the product on this 5th and final device.
I've tried removing the software, re-installing, doing a Disk Repair (in safe mode), and removing the software again.
This 5th machine (of 5) is running macOS Catalina, version 10.15.4.
Any ideas on how to get my full entitlement of 5 Macs successfully installed & licensed (only 4 out of the 5 appear to allow to be licensed)?