Hi RoseNies,
Thanks for reaching out to Microsoft Community and posting your inquiry. We have removed the PII on your post.
Surface docks has warranty, if the troubleshooting below doesn't work we suggest to reach out the Customer Support to check your warranty status and exchange options. We suggest the methods below to troubleshoot the dock issue:
- Run Surface Diagnostic Toolkit.
- Run the System File Checker.
- Clear your display cache. Undock your Surface from the Surface Dock or disconnect the monitor from your Surface. > Download the Surface Dock registry file. Choose to Open the file. This file will clear your cache, whether you have a dock or not. > Select and run surface dock registry.reg. > Select Yes to allow changes to your Surface, select Yes to confirm, and then select OK to close. > Restart your Surface, reconnect the Dock and/or monitors, and try your external display again.
Keep us updated by replying on this thread.