How do you reclaimproperty that was sold in sales tax to a bidder. That has reach right of redeemtio

How do you reclaimproperty that was sold in sales tax to a bidder. That has reach right of redeemtio...heir property was sold in 2005 tax sale. right of redeemption ended May 30, 2009. we just found out property was sold in june. we contacted the person who purchased the land on june 16. she picked up deeds on june 17. she is slow to respond to our request about reclaiming the propery. What should we do. do we have any legal rights.