You can go through the same steps you followed to connect your wallet:
- In the MetaMask browser extension, click on your account to open the "Select an account" screen. Then click "Add account or hardware wallet" → "Add hardware wallet". In the next screen, click "QR-based" and click "Continue".
- Because you already have a hardware wallet synced, you will get a list of your ETH accounts instead of the camera.
- Below the list of ETH accounts is a link "Forget this device". Clicking this link will disconnect ZERO from MetaMask.