FA appeals to Ivy League universities rarely succeed as they already have very generous awarding processes. You chances will depend on whether (1) your circumstances have changed materially since you applied; (2) you can convince them that they misunderstood some aspect of your financial situation; or (3) you made an error in your CSS or FAFSA that you want to correct.
Note that what universities determine to be your expected contribution may not be what you think you can or should pay!