While it doesn’t influence our opinions of products, we may receive compensation from partners whose offers appear here. We’re on your side, always. See our full advertiser disclosure. Image source: Getty Images In the last year, the government has authorized a substantial amount of COVID-19 stimulus money. These direct payments were a lifeline for families struggling due to the pandemic.However, some people didn't get the full payment they were owed. If you're one of them, you still have the opportunity to claim your money. However, first you need to know you were paid an incorrect amount and then you'll need to take action by claiming your Recovery Rebate Credit when you file a 2020 tax return.In fact, even people who don't normally file returns will need to do so if they are missing part of their stimulus payment and want to claim it. Here's how you can tell if that happened to you.How to figure out the correct amount of your second stimulus paymentThe second stimulus check was $600 per eligible adult and $600 per eligible dependent. Dependents counted only if they were under 17, so if you have college students or elderly relatives who you claimed as dependents, you won't get money for them. Unfortunately, they also aren't eligible for checks, as anyone who was claimed as a dependent doesn't get one.To figure out the amount of money you should have received, multiply the number of qualifying adults and dependents in your family by $600. So if you are single, you'd be entitled to $600. But if you're married with two kids (four people), your household should have gotten $2,400.For many people, that's the end of the calculation. But there were income limits for the second payment. If your income was below $75,000 as a single filer or $150,000 as a married joint filer, you'll get the full amount determined by the math above. However, if your income is above this threshold, you need to reduce the amount at a rate of $5 per each extra $100 earned.For example, if you're a single filer with an income of $76,000, you earned $1,000 above the threshold -- 10 extra $100S. Since you lose $5 for each extra $100 (5x10), you would get a stimulus payment of $550 instead of $600.Single filers who earned above $87,000 and married joint filers with incomes above $174,000 will not receive any of their own payments based on the phase-out rules, although it is still possible to receive some of the dependent money depending how high income is.What to do if you didn't get the right paymentIf your second stimulus check was for the wrong amount, the IRS will not automatically correct its error and deposit the additional funds in your bank account. You'll have to file a 2020 tax return. When you do, you'll claim the remaining payment.See, the payment was actually an advance on a tax credit. So you can get the missing money by claiming the Recovery Rebate Credit. You'll need to do this even if you ordinarily wouldn't file a return, as it's the only way to get your hands on the money the government owes you.When you file your return, you'll have to provide information on the amount of the stimulus payment you already received. That way, the IRS can determine how much it owes you. The IRS indicates you can find out how much you received already by creating or signing into your online account.Finally, you should know that while the IRS used past tax return data (from 2018 or 2019) to calculate the second payment when it was distributed, they will use the information from the 2020 return you file to calculate your Recovery Rebate Credit. In other words, if your income changed between 2019 and 2020 and that change impacts eligibility for payments, be aware that the new numbers on your 2020 return are what count.Top credit card wipes out interest until 2022If you have credit card debt, transferring it to this top balance transfer card can allow you to pay 0% interest for a whopping 18 months! That’s one reason our experts rate this card as a top pick to help get control of your debt. It’ll allow you to pay 0% interest on both balance transfers and new purchases until 2022, and you’ll pay no annual fee. Read our full review for free and apply in just 2 minutes.We’re firm believers in the Golden Rule, which is why editorial opinions are ours alone and have not been previously reviewed, approved, or endorsed by included advertisers. The Ascent does not cover all offers on the market. Editorial content from The Ascent is separate from The Motley Fool editorial content and is created by a different analyst team.The Motley Fool recommends Bitcoin. The Motley Fool has a disclosure policy.Source