Datatable "Select all" checkbox checks checkboxes only for few seconds

I'm having an issue with Datatable selecting all checkbox rows. At the top of my table i have a checkbox with the id "select all". Each row of my table has a checkbox which is by default not checked.

This is the code i use to check all row checkboxes:

$('#selectAll').change(function() {
    if( $(this).is(':checked') ) {
        $('.row-checkbox').prop('checked', true);
    } else {
        $('.row-checkbox').prop('checked', false);
    }
});

My issue is: after clicking on the select all checkbox, the checkboxes of all rows get checked, but only for 2 seconds, and they go back to unchecked. And ofcourse i want to them to stay checked. (page is not being refreshed or anything).

Does anyone know this problem? And/or know how this weird issue can be fixed? Or could point me in the right direction?

Thank you very much!!