Deliberately ignoring your salary pay date

So this is how they operate: I state clearly that my salary date is the 24th of each month. They insist, even after numerous emails and receipt of bank statements, that it's the 17th or 19th, depending on some arbitrary algorithm. What it's really about is increasing your interest rate on your next loan, because you haven't paid them back on the 19th. Because your salary only arrives on the 24th. This is deliberate.