302-466-5623

I do not know anyone in Delaware,  I did not answer, they did not leave a message.

Received call from another number. Then given this number to call 302-466-5624. Was told that I was being sued due to an unpaid payday loan in 2015. Stated I paid most of the $250 toward $500 loan. Seems odd I wouldn’t pay the full amount  if I paid half. I can’t say for sure right now, but I could have been scammed. Not by them so to speak, but by the original creditor. I will do more research.

I don't know how you could have been scammed by the original creditor.  I also can't believe that you don't remember taking a loan out, especially one with that high of an interest rate.  But regardless you don't have to do anything:

It is incumbent upon them under the law to prove that the debt exists and that you owe it, and (this is the important part) that they have the legal right to collect it.  You are not obligated under the law to prove that you don’t owe or that it is paid.  

Federal law (FDCPA) requires them to send you a letter, email, or text (postmarked in the case of a letter) within 5 days of their first contact that contains their name, physical address, the creditor’s name, and the amount of the alleged debt. Unless they have communicated it to you verbally at the beginning of your conversation. It also must contain the “mini-Miranda” telling you that it is an attempt to collect a debt and that all information will be used for those purposes. The one other important thing that this communication must also have in it is that you have a right to dispute the debt within 30 days of receipt of the letter and if you do so, all collection activity must be stopped until the debt is verified. If and when you get that communication you should immediately send that debt validation letter by certified, return receipt mail.

First, you should make a complaint at this Federal Agency, and while there you should also read up on how debt collection is supposed to work as well as what your rights in this matter are: https://www.consumerfinance.gov/

Also file a complaint with your State Attorney General's office.
List of State AG’s offices:   https://800notes.com/faq/attorney-general

They claimed to be a lawyers office

Caller didn’t leave message .  Seen from other replies it is a credit/debit collector or scam

I can confirm this is a scam. They said I opened an account through cashnetusa and had my drivers license number. I live in California. I called cashnetusa and they said they don’t even service California. So there’s no way that an account could even be opened using my drivers license.