Inadequate funds on CPFF Contracts

My Contracting Office is notorious for inadequately funding my fixed fee pools on my CPFF (Completion Form) contracts. Currently, I have several which have recently ended or are coming to an end and my fee pool is nowhere near fully funded. I send letters/emails, make phone calls to my CO and I am consistently told the "funds are coming" or "the customer has no additional funds presently available."

How do I avoid this problem from continuing to occur? What avenues do I have which will lead to the Gov't getting the majority (if not all) of my fixed fee funds up front?

Thanks!