Clip exports bypassing original source timecode and defaulting at 00:00

Hi there. When I export a short selection of my video straight out of the source window, the new clip starts at 00:00:00:00 completely ignoring the original source timecode. I even have a timecode generator on the clip which shows the correct timecode. Any ideas on how to resolve this issue that I have never experienced before until today, I would be greatly appreciate. Thank you.