I would be surprised if the lender has a legal claim to enforce the purchase agreement you entered into when you bought your dining room set 13 years ago. Every state has a statute of limitations which limits the amount of time during which a creditor can file a lawsuit against a debtor to enforce an unpaid obligation. For example, California law gives creditors four years to sue for the enforcement of a debt; only a couple of states, Ohio and Kentucky, have a statute of limitations longer than 13 years. Therefore, the company trying to collect on this old debt probably has little ability to legally force you to pay the check it failed to cash 13 years ago. Read this Bills.com resource to learn more about statute of limitations for debt.
Even if this creditor somehow were able to proceed with a lawsuit and obtain a judgment against you for this old debt, it would likely be difficult for the creditor to enforce its judgment. Like most other forms of retirement income, Social Security benefits are generally exempt from garnishment by judgment creditors, so there is little chance that the creditor could force you to pay it from your limited income. Given the age of this debt and your limited income, I think it highly unlikely that this creditor will continue trying to collect this debt. However, if you begin receiving collection calls, you can send a cease and desist letter to the creditor, which should help stop the calls.
You may wish to respond to the letter you received, stating that the statute of limitations for the enforcement of this contract has expired, and that the collector must cease all collection activity. In addition, you may want to detail your financial situation, explaining the fact that in the thirteen years that have passed since this transaction was originally conducted, you have retired and are living on a small social security benefit, and thus are unable to pay even if you were liable for the debt. You may wish to consult with an attorney about this matter and have him/her respond to the collector on your behalf. Given your age and limited income, you may qualify for low-cost or even free legal representation through your local Legal Aid office. Your state or county bar association should be able to advise you of available low-cost legal resources for seniors in your area.
In all, I think that you have little to worry about in this situation. The debt is almost certainly past the statute of limitations, and even if it were not, your income is likely exempt from garnishment. You should probably reply to the letter and then put this out of your mind, as you will likely never hear from this creditor again. I wish you the best of luck in resolving this claim, and hope that the information I have provided helps you Find. Learn. Save.