CP268 tells you we made changes to your return because we believe there is a miscalculation on your return. A CP12 Notice is sent when the IRS corrects one or more mistakes on your tax return which either result in a different refund amount, or in an overpayment.The CP05 notice is mailed to taxpayers notifying that the IRS is holding their refund until the accuracy of the tax return's been verified. You can find the CP or LTR number on the right corner of the letter. The IRS issues most refunds in fewer than 21 calendar days. You can check the status of your refund with "Where's my refund?" on IRS. Do you have a balance and need help resolving it? You may find the information below helpful in resolving your balance. You must contact the IRS within 60 days of the date of this notice, for IRS to reverse the changes made on your account. A waiver waives out- of-state residency costs and allows the student to pay in-state fees.