i have just brought a new computer and monitor and i can not get the monitor to work until i close screen down on the computer

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May I know your first name, please?

Nice to meet you, *****!
Do I understand correctly, do you have a MacBook and external monitor for it?

Konic monitor? Got it.
Try using Command + F1 to toggle mirroring on/off. You must be logged into a macOS user account before this key combo will work.
Please let me know once it's done.

Great to hear:)
Is there anything else I can do for you today?

You too!
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