Terrific response, as always! Thank you so much.
Posting answer here just in case someone else might need it someday.
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i corrected this by updating the store/admin/home.php page. i changed the query for the monthly_revenu recordset from:
$query_monthly_revenu = "SELECT SUM(OrderAmount) as monthlyTotal FROM ps4_orders WHERE MONTH(NOW()) = MONTH(OrderDate) GROUP BY MONTH(OrderDate)";
to:
$query_monthly_revenu = "SELECT SUM(OrderAmount) as monthlyTotal FROM ps4_orders WHERE MONTH(NOW()) = MONTH(OrderDate) AND YEAR(NOW()) = YEAR(orderDate) GROUP BY MONTH(OrderDate)";
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