How to setup Nuendo to play VSTis with USB Keyboard

Hello, I’ve been using Nuendo for audio post-production for quite some time. For composition, I’ve mostly used other DAWs until now. I’ve started working on a song with Nuendo again, and I’m facing the same issue I’ve encountered before, and I feel completely lost once more. Maybe someone can help me understand this once and for all.

Could someone please write or provide a checklist for me, or link me to one, outlining what I need to activate in Nuendo for a very basic setup (monitoring, MIDI Thru, etc.) so that I can simply play VST instruments with a USB keyboard?

I have a keyboard connected to the computer via USB.
I can see MIDI arriving in Nuendo at the bottom right and in the MIDI Monitor window.
I also hear sound when I click the keys directly in the VST instrument.
However, it seems like the MIDI signal is not reaching the instrument because when I press the keys on the hardware keyboard, none of the VST instruments produce any sound.

Don’t be afraid to share more details :wink: .

Are you using an instrument track? What is the VSTi you are using? What is the input set as for your track? What is the actual input device (MIDI controller/keyboard?) you are using?

Screenshots could also help.