Releasing A Lien For Money No Longer Owed.

I bought a condo that was part seller financed in 2013. I paid off the seller financing over 12 months. The seller signed a Certificate of Satisfaction stating that the financing was fully repaid but it was never notarized. I have gone back to her asking to agree to the notarization but she is in her 80's and expressed resentment at the sale and is refusing to acquiesce to the notarization. Just to clarify her daughter was involved in all this because it was written into the financing that should she decease I would pay what was owed to the daughter. Both she and her daughter signed the Certificate of Satisfaction. All this means she still has a lien on the property even though nothing is owed to her. Is there anything I can do to relieve this situation.