There are a few reasons why your dashboard balance (Funds Remaining / Overspent) might not match the actual balance of your Tracked Accounts. Here are a few things to check:
1. Make sure every transaction on the Income and Use of Money tabs has a Month assigned.
2. Make sure the Category and Income Source columns are filled in.
3. Reference your tracked accounts online to check for typos or missing transactions.
4. Sort your transactions by Amount to look for duplicates
5. Make sure you entered a Starting Balance on your Annual Overview page, and that it's correct.
6. If you're using credit cards, make sure you're not tracking both purchases and payments - this would duplicate your amounts.
See this article for more information about how to track credit cards.