The first thing to do would be to check if the system has the correct location.
You can check that by confirming that your current location is selected in the location drop down from the My Checklists Page.
If there is no location, or an incorrect location, selected then you won't see what you are expecting to see since checklists are assigned to specific locations. Then proceed to click on the dropdown and select your correct location.
If that still doesn't work, log out and then log back in.
If you continue to still have issues, you will need to contact your system administrator to ensure that nothing has changed in regards to your account access.