Table Sort by Number showing incorrectly

I have a table with several groupings on the left. The table is used to sort candidates applying for a job by the step of the process they are in.

The far left column is the step number, and the table is first sorted by that Step number in ascending order, and then by other parts of the table. When the table is displayed however, it loads out of order. When I refresh the tab, sometimes the order changes (sometimes to the correct sort, other times to a different and incorrect sort).