On your Dashboard
1. You aren't looking at the correct site - check the site dropdown at the top left
2.You aren't looking at the correct date range
3. You've turned off showing your shifts
On the roster page
You are using a view that doesn't show the shifts you want to see
Anywhere
Your shifts haven't been published yet
non-admin users typically can't see unpublished shifts that are in draft state. Maybe your admin hasn't published them yet?
You don't have the correct permissions
you might not have the permissions to see the shifts at all
you might not have permissions to see the shifts based on their status - example, they are in draft state
What to do? Talk to your administrator