Old Mutual Unwilling to pay out policy

We have been trying for 4 months to cash in a policy without success. Old Mutual has put unusually complicated and changing requirements in order for us to do so. Every time we send additional required information we are told something else is wrong with our application. Old Mutual tell us that disinvestments are handled by an outside company so these problems are "out of their hands". This is absurd! We have cashed in policies from other insurance companies within 3 weeks without any issues whatsoever.