How do I enter multiple payments for one pledge?
Click to expand the pledge payment schedule and then click edit on the expected installment set up for next year - you can change the date back to the current year. 

Unless you are dealing with multi-year pledges, consider creating them with a single installment to occur every one day - in this way, the system will transfer the remaining balance as being due the following day as opposed to the following year.

Hope this helps,
Tamar