Amended return resulted in balance, but got two IRS notices

Hello!

 

I amended my 2021 joint return, but I got a notice from the IRS saying that I still owed around $30 (including interest).

 

1.  I received two notices that look exactly the same and with the same amount due, but one is addressed to myself and another is to my wife. However, the last 4 numbers of the SSN on both notices are mine. Does that mean I have to pay both notices, or is it just a duplicate notice because I filed jointly and I only need to pay one?

2. The notice says that I can just mail a check with some information written on it. I don't need to fill out a whole new form as well, is that right?

 

Thank you!