I paid my taxes owed on time and have the canceled check in my bank account show that it has been posted. But yesterday I received a bill from the internal revenue service saying they haven’t rec

[Anonymous]

this could simply be a situation where the IRS got your return but processed the payment later so the IRS computers automatically sent out the notice.  you have 3 choices.  1) there is probably a number on the notice to call.  with the check copy in hand - front and back - you could try calling to see if this can be resolve over the phone.  with the info on the check the agent should be able to track down that the IRS got the payment.  the usual cause is incomplete or incorrect info on the check or an entry error by the IRS personnel who processed it.   in the future you may want to use IRS Direct Pay to avoid this issue.  2) send back the notice with a copy of the front and back of the check. do this ASAP. 3) use TT audit support    https://support.turbotax.intuit.com/irs-notice/audit-support/