Hi,
If your TV is displaying lines on the screen, we recommend the following steps to help isolate the issue:
1. Check all input cable connections for any external devices (e.g., HDMI, streaming boxes, Blu-ray players)
2. Switch channels or inputs to see if the issue appears across all sources
3. Run a Picture Test to check for panel-related issues: Settings > Support > Device Care > Self Diagnosis > Picture Test
4. Perform a cold boot by holding the power button on your remote for about 10 seconds
5. Ensure your TV has the latest software installed: Settings > Support > Software Update
If the issue continues after these steps, the TV may require service. For further assistance, please contact Samsung Support at 1-800-SAMSUNG, 8AM – 12AM EST, 7 days a week. LiveChat and additional support resources are also available through the Support link on our website.
~Samsung Advisor