macOS doesn't print as long as Windows is running

Hello
I have an issue with a Parallels installation where Windows 10 is the guest on macOS. The issue arose recently, before it worked normally for more than a year.
The issue is with a Brother Printer that is connected to the iMac via USB.
When Windows 10 is running, I can' print (or scan) on macOS. Print jobs will just stay in the queue, saying "waiting for printer to become available".
As soon as Windows 10 is shut down, the printing starts and the queue is processed.
Windows prints & scans normally.
Any idea how we can print again form the macOS host even if Windows guest is running?
Thanks