Hello ivor114,
For difficulties with your Mac Studio detecting your monitors, you'll want to take the steps below:
Check your cable or adapter
Disconnect the cable from your external display from your Mac, then reconnect it. If the cable from your external display doesn't connect to the ports on your Mac, you can use a USB-C or Thunderbolt adapter. If you're using a USB-C or Thunderbolt adapter to connect a display, the adapter must be compliant with DisplayPort Alt Mode or Thunderbolt / USB 4.
Check how many displays you can connect
If you're connecting multiple displays to your Mac, use the Tech Specs page to find out how many external displays your Mac supports.
1. Choose Apple menu > About This Mac, double-click your serial number, then press Command-C to copy it.
2. Go to the Tech Specs page, click the Search Tech Specs bar, press Command-V to enter your computer's serial number, then click Search.
3. Click the specs page for your Mac. The number of displays your Mac supports appears under Video Support or Graphics.
You can also find those steps in this resource: If your external display isn't detected or appears blurry when connected to your Mac - Apple Support
Should that still persist, does it also continue if you boot your Mac into safe mode using the steps below?
1. Shut down your Mac.
2. Turn on your Mac and continue to press and hold the power button until you see the startup options window.
3. Select your startup disk, then press and hold the Shift key while clicking “Continue in Safe Mode.”
4. Log in to your Mac. You might be asked to log in again.
This resource also covers those steps: How to use safe mode on your Mac - Apple Support
It can take a few extra minutes to boot into safe mode. Your screen may flash or flicker while in safe mode. Those behaviors are expected. Testing in safe mode runs a check on your disk, removes some cached files, and can help isolate conflicts with startup items. Once you've tested that in safe mode, you can restart to leave safe mode.
Let us know your results, and we'll keep moving forward from there.