To enter credit card....
The proper way is to set up a credit card ACCOUNT and enter the charges into it when the purchase is made and assigning it to a category. The transactions need to be entered with the date you charged it, not the date you pay the credit card bill.
Then when you pay the bill you TRANSFER the payment from your checking account to the credit card account. Then when you download the payment from the bank you match it to the one you already entered. Then your credit card account should match what you actually owe at any time.
When you enter the payment in your checking account you put the credit card account name in for the category using square brackets around the name to indicate it is a transfer...like this… [credit card] or newer versions have a Transfer column.
First make sure you are sorted in Date order with the newest date at the bottom. If you are not then click the DATE Column heading to sort. Sounds like you're running a credit balance. Is the balance in red or black? Look back through your transactions and maybe you'll spot one that was entered backward. Or a payment in the charge column or a charge in the payment column. Look around back where this first started happening. Or maybe you are missing some charges? If the balance is in Black, it means you have a credit on the card. Like if you overpaid the bill or got a refund for something you returned. When you enter a charge it will reduce (decrease) the credit you have available on it. And a payment will increase the balance.
Also make sure you have the right starting balance. If it's zero you might need to add a beginning balance for when you started the account in Quicken.
The credit card balance you OWE should be in RED. If the balance is Black then it's showing the credit card company owes you and you have a credit balance. And then when you make a payment it's like the cc owes you more. So you need to go back though your entries and find where the balance switched to black to being in your favor.
See this for more info.....
https://www.quicken.com/support/positive-black-balance-credit-card-account