(Sorry my english not good) I run "Tom Clancy's Rainbow Six Siege - Terrorist Hunt - Terrorist Hunt Classic" and submit succeed. But my date and leaderboard are not match. If adm didn't know what my say. You can watch this img

This appears to be a result of the filters hiding one of the runs, the actual 1st place run has no difficulty selected, and does not appear unless you tick 'Any' in the first difficulty in the drop down menu for filters. The filters could really use some cleaning up though, as difficulty is listed as a filter 3 different times.