Address issue,SLC

Hi, my name is Rafsan. I received an email yesterday from SLC, asking me to send my Father's ID card or European passport as because you’ve applied under a category that is
dependent on your relationship. I sent my dad's European ID card. The email I got yesterday from student finance said to send evidence to this address
Student Finance England
P.O. Box 311
Darlington
DL1 9NZ
But when I log in to my student finance online account, it also asks for evidence and there is an option named Evidence Cover Letter and it says that I should print and send the Evidence Cover Letter paper along with the evidence to this address.
Student Finance Services European Team
Student Loans Company
PO BOX 89
Darlington
County Durham
England
DL1 9AZ
But, the online evidence Cover Letter and the email I received from SLC yesterday, both have different addresses. I called SLC and asked them what address I should send it to. They told me to write to the address given in the Evidence cover letter means
Student Finance Services European Team
Student Loans Company
PO BOX 89
Darlington
County Durham
England
DL1 9AZ
I sent my evidence to that address. I did not send my Father's EU ID card to the address which was written in the email I received from SLC. Did I do something wrong?