What should I do if my extension request has been rejected and I only noticed after the deadline?

[Rachel_W]

If your extension rejected, you should print and mail it. You have until April 20, 2019, to do so and it will still be considered filed by the deadline.  There is a five day grace period when your extension rejects.

[lucasdemarchi]

Should I also send the payment or will it work via ACH I had requested?

[Rachel_W]

Yes, you should also sent the payment.  If your extension was rejected, the payment information was not received by the IRS.