aprs.fi, by default, limits the length of any track to the most recent 1 hour time period. On the right side of the page is a pull-down box labeled "Track tail length". If you change it to a longer period of time, you are more likely to see tracks.
As I type this, it's 4 am in Spokane. I wouldn't expect many APRS position reports in motion at this time of day. And, the default 1 hour track setting on aprs.fi shows nothing in motion. But, if I change the Track tail length to 12 hours, I see a couple tracks.