If it has been over five years, OSI cannot collect on this debt through legal action. If they try, you will have an affirmative defense. However, you will need proof. Do you have a credit report from a credit bureau? If not, you should order one from Equifax, Experian, and TransUnion. Order it from each individual credit bureau, and do not do a trimerge.
Also, send a letter to OSI certified mail return receipt. Tell them you are requesting proper validation as per the Fair Debt Collection Practices Act. If they actually send validation, you should have proof of the date of last activity. If the debt is in fact past SOL, send them a full cease and desist letter, again certified mail return receipt.
However, I highly recommend getting proof of the date of last activity, just in case, before sending the cease and desist.
