Hi,
Please do try these troubleshooting steps that may help.
- First, while the laptop is connected to the TV press the Windows key + P at the same time and select between Duplicate or Extended display then press Enter.
- If it will still not work, do a clean install of the graphics driver.
- Go to Device Manager and uninstall the graphics driver.
- Next is to open Programs and Features then uninstall anything related to the graphics card.
- Once uninstalled, download and install the latest driver.
- Reboot the laptop once installed then test it again.
- If the same problem will persist do try changing the cable or even try a different monitor.