What should I do if IRS issued me a check for the exact same amount of my Form 1040-ES check, after accepting the same?

[VolvoGirl]

You made a 1040ES payment?  For 2018 on a 2018 1040ES?  Did it show up on your 1040 line 17?  If it showed up on line 16 the IRS thought you didn't include it so added it into your refund.

[vabhijit]

Yes, I made a 1040ES payment for 2018, on a 2018 1040ES. It did not show up on line 17 on the 1040. Line 18 includes the amount that I had mailed in.

[VolvoGirl]

Do you remember entering the estimate payment?  Did it show up somewhere else like on line 16?  Wait a minute?  It is included in line 18 with your other withholding, etc?  Then definitely double check line 16.  The IRS added it on line 17 for you.  But if it was already in your return (on the wrong line) then eventually the IRS will see it and ask for it back.  They will say you reported too much on line 16.  

[Anita01]

Accepting only means the IRS was able to identify you as the filer and they ran a few math checks.  It does not mean they accepted all your calculations or the amount you paid.  Apparently, when they processed your return, they felt you paid too much and refunded some of it.  You don't need to do anything.