Hi Bonbon, Thank you for sharing your experience with Samsung’s U7900F. 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 – 9PM EST Mon – Fri, 8AM – 6PM Sat – Sun. LiveChat and additional support resources are also available through the Support link on our website. ~ Samsung Advisor

Hi Chyyna, Thank you for reaching out to us. If your U7900F TV’s Smart Hub is freezing, lagging, or not loading properly: 1. Reset Smart Hub – Home > left directional key > Settings > Support > Device Care > Self Diagnosis > Reset Smart Hub (This will sign you out of apps and reset Smart Hub to factory default.) 2. Update firmware – Home > left directional key > Settings > Support > Software Update > Update Now 3. Run Device Care – Home > left directional key > Settings > Support > Device Care > Start Device Care If the issue persists, contact Samsung Support at 1-800-SAMSUNG, 8AM – 9PM EST Mon – Fri, 8AM – 6PM Sat – Sun seven days a week. You can also connect with a LiveChat agent by clicking the ‘Support’ link on our website. ~ Samsung Advisor