If you benefit from your deceit both civil and criminal punishment is possible. Do not post any details online because of potential self incrimination problems for you. Get a criminal defense lawyer on your side. Your lawyer will tell you not to speak to the police. If you confess to a crime you did not commit (trust me, it happens), you will be charged.
Everyone has a freedom against self-incrimination but an online site like this one is not private. What you post here may be used against you. No one can say what the evidence is against you so at least remain silent and do not incriminate yourself without speaking to a lawyer.
Read my Legal Guide "Internet Privacy - Not!" if you think it might be helpful.
You need a lawyer so get one. ASAP!
Read my Legal Guide "What is the Right to Remain Silent?
Because this matter is so important you should really get a lawyer. Many factors such as age, prosecutor discretion, what judge you have, whether witnesses are credible all matter and that makes it near impossible to say what type of time you'll do if this is crime, if any.
You can miss defenses and say the wrong things if you are not represented by an advocate as your attorney.
You might find my Legal Guide helpful "How to Choose A Lawyer For You"
You might find my Legal Guide helpful " What Do I Tell My Lawyer"
No one can know what the record is in the case because online we cannot find out any details about the loan or the investigation into the account that was done. You need a lawyer. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
NOTE: This answer is made available by the out-of-state lawyer for educational purposes only. By using or participating in this site you understand that there is no attorney client privilege between you and the attorney responding. This site should not be used as a substitute for competent legal advice from a licensed professional attorney that practices in your state in the subject practice discipline and with whom you have an atttorney client relationship along with all the privileges that relationship provides. The law changes frequently and varies from jurisdiction to jurisdiction. The information and materials provided are general in nature, and may not apply to a specific factual or legal circumstance described in the question.
If you think that perhaps you did not pay off a payday loan in Utah, you might contact a Utah lawyer to see if such things can result in criminal charges in Utah (where I am not admitted to practice; nor am I admitted in California). If so, they can advise you about the possibility of you having them contact the prosecutor's office to see if such charges are actually pending.
The person calling you may simply be a bill collector. If he is, and he is threatening you in that way, he may have violated federal debt collection law and/or state consumer protection law. Ask him to send you something in writing, but do not discuss the substance, if any, of his allegations with him. Then take what you have learned and consult a Utah lawyer about the possibility of criminal charges and a California lawyer about possible civil claims you may have.