Rear top Running lights not working

[Tim-Nancy-C]

The 5 running lights across the back top of the trailer are not working. Not a big deal except it powers the backup camera. The backup camera worked for a while when I hooked it up and then it stopped. I assume that what’s when lights failed. Troubleshooting I found the issue with the lights. Where would be a good place to begin tracing this. I checked fuses and breakers. All are ok. All other lights work. Just these 5 don’t.