Hi! I see you're having trouble with your Samsung smart TV showing an "error on set source" message for the last two months. To help you better, could you tell me a bit more? For example:

- Does this error happen when you try to switch to the TV5MONDE app specifically, or does it occur when changing any input/source?
- Have you been able to access the app or sources normally before this issue started?
- Are there any other symptoms like app crashes, screen freezes, or no picture?

Meanwhile, here’s a quick general approach we can try to troubleshoot this source error:

1. Restart the TV:
- Unplug the TV from power for about 1-2 minutes, then plug it back in and turn it on. This simple reset often solves temporary glitches.

2. Check the app:
- If the error is related to the TV5MONDE app, try uninstalling and reinstalling the app from the Samsung Smart Hub.

3. Check TV source/input settings:
- Press the Home button on your remote, go to “Source” or “Connected Devices,” and verify the correct input or app is selected.

4. Update TV software:
- Go to Settings > Support > Software Update, and install any available updates. Sometimes bugs causing errors get fixed this way.

5. Factory reset (if needed):
- If the previous steps don’t work, a factory reset might help. This option is under Settings > Support > Self Diagnosis > Reset. (Note: This will restore your TV to original settings and erase apps and configured preferences.)

If you’ve tried some of these already or want guidance on any specific step, just let me know! We can dig a bit deeper based on what you share.