First, connect your TV in your laptop via HDMI then press the Windows key + P at the same time and select between Extended or Duplicate display then press Enter. Also make sure that your TV is set to HDMI depending to where is it connected to. If these doesn't work do try to uninstall/reinstall the graphics card driver.
- Go to Device Manager and uninstall the graphics driver.
- In Programs and Features do also anything anything related to your graphics card.
- Next is to download and install latest graphics driver.
- Once installed, reboot your laptop for all the changes to take effect.