I found an answer from Presonus support team in my e-mail archive, which shows a temporary solution.
I quoted the e-mail.
Your question on has been answered by brianmeisner1:
There is currently a problem with the MIDI output ports in Notion and Windows 10. The issue has been logged with our development team in hopes that it might be resolved in a future update. In the meantime, please go to File>Preferences>MIDI and select "-" for all of your MIDI output ports. Once you have set your MIDI output ports to none, please close and re-open the program. If the ports are already set to "-," please set them to something else, and then back to the hash-mark. Close and re-open Notion.
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