I Paid IV fee $325 on CEAC website on June 2020.
My appointment was schedule for next week, and today I got an email to bring some documents and also $325 in cash for the consular fee.
I checked the Peru embassy website and the MRV fee validity was extended until September 30 2023 https://pe.usembassy.gov/visas/important-visa-information/
I didn't find anything about this payment online or in this forum, so I guess the consular fee is the same as the IV MRV fee, and the embassy has decided my previous payment is now expired and is requesting to be paid again?