Lien holder will not sign release upon payment

[Pinto]

What is the name of your state? Oregon
My ex will not appear to sign the release papers for a small lien even though the agreed upon amount of the lien has been available in a Title Co. She is being vindictave and wants to make things tough for me any way she can,as this affects my credit rating and insurance.
What steps can I take to get her to quickly take steps to sign the papers?

 

[JETX]

What steps can I take to get her to quickly take steps to sign the papers?

What kind of lien is it??
If a judgment lien.... simply make payment at the court and they will provide a 'Satisfaction of Judgment'. Take that to the county recorder and they will release the lien.

 

[Pinto]

Judgement lien

The lien is for six unpaid child support payments of $550 each or $3300 total.
All payments were made religiously over nearly ten years until child reached college age. When father found out that she had quit college he sent her a letter telling her that if she could show that she was still going to college and taking required credits he would continue the last six payments. No answer was forthcoming so he quit payments.
Oregon laws in such matters require students to report to Father providing support on grades and if they quit school. Father never received any information or correspondence for the years the child was in college but kept paying payments as he thought child was attending school. Unfortunately this was not handled through the Oregon Child Protective agency as the Oregon attorney that handled his divorce did not arrange it. Huge mistake in my opinion.
Mother is very vindictive and relishes in any trouble she can cause the Father,so she is guiding the child's actions in not signing the release of the lien even though the $3300 is waiting at the Title Co. for her.
He is buying a house and the lien interferes with the lender.
Is there any quick recourse?
Thanks a bunch for your advice.