My debt was sold to another collection agency.

My debt was sold to another collection agency and they sold it to another collection agency and now they do not know who they have sold this debt to because they did not document who they sold the debt to. How can I get rid of this debt off my credit report?
Thank you in advance
Debt sold to another collection agency
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"majors@oskie.com" / to Debt Sold / show details / Jun 27
http://www.oskie.com/free-letter/debt-validation-letter-collections-collection-company-agency.htm
Use this letter
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Debt sold to another collection agency / to me / show details / Jun 28
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