I’m Getting Sued By A Debt Collection Agency

I was recently notified of a lawsuit involving an alleged medical debt that I believe has already been paid. The debt collection agency is claiming that I owe approximately $2,300 for medical services. However, after reviewing my medical billing records, I found discrepancies between the amount being collected and what my medical provider shows I owe. The billing statements I have access to show that insurance and patient payments were applied to the charges, with the most recent itemized statement showing a remaining balance of $0. My online patient portal also shows that the accounts associated with my medical treatment have a $0 balance.
The legal documents were delivered to a family member at an address where I have not lived for several years. I currently reside in a different state and have established residency there. The documents were not personally handed to me, which has raised concerns about whether I was properly served. I was given a 10-day summons, but after contacting the debt collection agency, I was informed that the lawsuit had not officially been filed with the court at that time.
After receiving the documents, I contacted the debt collection agency to request an itemized bill and an explanation of the amount they are claiming I owe. I wanted to understand where the balance came from, what services it was associated with, and why it was being collected when my medical records show no outstanding balance. The agency informed me that they could only provide the requested documentation through regular mail and would not send it electronically. I requested that the documents be mailed to me, but I have not received them yet.
I also contacted the original medical provider to request clarification regarding the alleged debt. I provided information about the billing discrepancies and requested that they review the account to determine whether the charges were already paid or incorrectly sent to collections. At this point, I have not received documentation that clearly explains how the collection agency arrived at the amount they are demanding.
My primary concern is that I am potentially being sued over a debt that I have already satisfied. I do not want to agree to a settlement or make any payments toward a balance that has not been properly verified. My goal is to have the alleged debt investigated and, if the records confirm that it has already been paid or was incorrectly assigned to collections, have the balance corrected and the legal action dismissed or withdrawn.
I am also concerned about the legal process because the documents were delivered to an address where I no longer reside. I would like to understand whether the service was legally valid, whether the court has jurisdiction over the matter, and what steps I need to take to protect myself from a default judgment. I am currently looking into obtaining legal assistance to review the situation, determine what defenses may be available, and help resolve the matter without paying a debt that I do not believe I owe.

Please help I have no idea how to proceed

Location: Utah