Need legal help, debt, mortgage servicing

I am 70 years old and on a fixed income. I am barely getting by. Select Portfolio Servicing is demanding payment of an "escrow shortage" on my home mortgage loan dating from 13 years ago, and which is not a valid debt. 

I successfully completed my Chapter 13 bankruptcy and was discharged on January 31, 2020. Since then , my mortgage servicer has been demanding payment of almost $600 for their claim from 2011, which was either paid or denied by the federal court. 

Their claim is based on imposed home insurance, even though I had my own policy with Farmers Insurance. In 2024, I lost my insurance because Farmers Insurance and other companies are cancelling all home policies in my community and other parts of California. As a result, I am now paying for lender imposed insurance for 2024. 

However, I do not owe their claim of "escrow shortage" which dates from 2011. 

I can't afford an attorney, and the amount is too small for any attorney to take the case on contingency. 

I need help. 

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