My client filed MFS in 2018, she just received a CP2000 stating that she under reported her income by not claiming two 1099-R retirement  distributions. After checking my records the 1099-R were issued to her ex husband but they have her SS# listed. How do I go about trying to correct this if her ex husband is not cooperative. I am planning on answering the CP2000 as no we don't agree with their finding with an explanation but I feel without an image of the 1099-R that will go nowhere. Any helpful suggestions will be appreciated.