Please HELP!!!! We purchased our home in 2004. State Farm wrote and has maintained our homeowners policy. Now, we''re told it was the WRONG policy

State Farm contacted us to inform us that for the past 7 years they had us under the wrong policy. They wrote us up as being a stick built home and not as a mobile home. Keep in mind they came out to the home site, did their inspection, took pictures etc... now we''re being told that they had no idea it wasn''t a stick built home. We have been insured for $145,000 now, they say they are going to rewrite our policy at only $60,000. We still owe 94,000 on our loan with BOA. State Farm said we will have to put $35,000 in the bank in order for BOA to continue our loan. We do not have that kind of money so I need to know what recourse we may have or do we need to give our home back??? My father is also going to have to do the same thing because his as well was written the same way. We would never had known had we not contacted them about our roof caving in. They of course said it''s a builders or manufactures problem. Neither one of them are in business anymore.. Desperate for any answers!!!