Case Approved

what's wrong with I-824?
my I130 case has approved 1 month ago,but following approval notice, uscis wants us sending I824 approval form to send it to nvc, anyway we sent it by post without paying money.do we have to pay money for 824??? some where I heared it is an error of uscis for this notice! what should I do?I am really counfused.heeelp

IR-1/CR-1

U.S. citizen filing for a spouse

Total Days: 591 days
Case
2021-01-09
2022-08-23
I-130
591 Days
Texas Service Center: I-130