I'm assuming you mean 3 shifts, not 3 blocks...shifts only update with payments when blocks are solved.  Since shifts only last 40 minutes, and block solves can take anywhere from 1 second to 3-4 hours, it's not unusual for 2-3 shifts to have 0 blocks paid when they're at the top of the Open Shifts section.  That is why there is a large BOLD NOTICE stating this exact fact.