This is a customer to customer forum so we have no idea. I would log into your DirecTV account online to see if the payment shows posted, in case the email was in error. If the payment does not show on the account go to www.directv.com/paymentdispute to fill out their webform to look into.
If your account online shows the payment, but still reflects past due, then call DirecTV 1-800-531-5000 to discuss the account to see if the payment was for a previous balance and have gone past due again or if something else is going on.
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