why is my projected balances graph is incorrect.

The Projected Balances graph is a projection of cash balances, not just the actual cash balance in your account.  It takes into consideration the current cash account(s) balance, uncleared register transactions, future dated manual and auto entries in the register(s) and the Bill, Income and Transfer Reminders you have set up.  So, it is normal, in most cases, that the Projected Balances graph will be different from your current checking account balance.

There are many things that can cause your projected balances to be lower (or higher) than what you think it should.  The first place to check is your Bill, Income and Transfer Reminders.  I you have Bill Reminders but no Income Reminders then your checking account balance projection will be lower than you think it should.  The reverse is also true if you have Income Reminders but you do not have Bill Reminders set up for all of your bills (at least for the big ones).  Make sure your Bill, Income and Transfer Reminders are completely set up with the correct dollar amounts and due dates. 

Also, make sure that you don't have any past due reminders because those will also be accounted for in the Projected Balance graph making the checking account balance look lower that what you think it should be.  If you have any of these, either change the due date so it is no longer past due, delete the reminder or ignore it, whichever is most appropriate.