I have two of the same loans?

I was paying Nelnet for years on a loan. In 2024 I paid it off and thought it was done.

Looking at my bank statements today I noticed a charge from Dept of Education. Looking on the studentaid.gov website and from what I can tell, its the exact same loan that I paid off on Nelnet.

Same timeframe, same interest rate.

What can I do here? How can I prove this is the same loan? It was over 13 years ago. There's no way I applied for two loans at the same time from the Dept. of Education.