Lennar Financial Services, LLC Mortgage Complaint

Lennar Financial Services, LLC Mortgage department,

Other mortgage Settlement process and costs Florida

I sold a property in Florida 3 months ago. Today I received a call from the broker who did the closing asking me to pay a household insurance for $ -.that was part of the selling agreement. My realtor with the broker check all paperwork and they told me that everything was in order and we finalized the transaction. I am a - citizen living in Social security and cant afford to pay that sum with my actual income. Do I need to pay for their mistake?