How to get a lien holder to sign the documents

I bought a house in California several years ago. The person from whom I borrowed money to finance the purchase had placed a second mortgage lien on the property. Now, I am trying to pay off the balance on her loan through cash out refinance and have the lien released. The lender and the title company tried to get her to sign the papers. She was irate that she was getting frequent calls and emails. She has become unreachable and uncooperative for signing the papers with the title company. I have tried all means to explain that this is time-sensitive. I have few days to close the loan and I am not sure how to resolve this issue. Any advice is appreciated.