1-1-1970 Paydays

Hello, trying to populate paydays and using the following formula but its returning 1-1-1970 no matter how I rework it.  Was trying to work through pay periods of the 1st through the 15th is paid on the 25th and the 16th to end of month on the 10th of the next.  The simpler part, for me, is that all the approvals are put in just before those pay dates so just trying to shortcut that anything approved before the 10th pays on the 10th and anything after, on the 25th.  I appreciate any assistance on this.

var number DayOfMonth = Day([Pay Approved]);
var number MM = Month([Pay Approved]);
var number YYYY = Year([Pay Approved]);

ToDate($MM & If($DayOfMonth <10,10,25) & $YYYY)

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Tyson Hayes
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