CP268 tells you we made changes to your return because we believe there is a miscalculation on your return. You make payments online at the following.You get an overpayment credit when your tax payments exceed what you owe. You'll automatically receive a refund of the credit. I called the number on both documents, 410-260-7980. And found out that due to COVID the phone lines are closed until further notice. Get free tax help from the IRS. File your taxes, get help preparing your return, help yourself with our online tools, find your local office – or call us. The effect of this action will cause any State income tax refund otherwise due you to be intercepted and applied toward your indebtedness. Explore options for getting your federal tax refund, how to check your refund status, how to adjust next year's refund and how to resolve refund problems.