Sort by ID Number not working

I've created a column with 7 digit ID numbers next to the student names. I want to sort by these ID numbers. Nothing happens when the column is selected in sort.

Name sort works.

I also, created a new column with numbers 1-9 which doesn't sort.

The quiz columns which contain values seem to work.

What am I doing wrong?

Thanks

Hello kvento,
You should make sure that the grade type for the ID column is set to 'Generic grade (numeric)'
Double tap on that column > Grade type and give it a look.
Please keep in mind that the sort by a column option will always put the highest numbers first