Wrong Smart Device Invoice sent

I purchased a Ipad in 2012 from fnb,i lost my icloud password so i contacted apple and the requested the invoice so i called fnb and waited over 30mins and got bounced from one dept to the next! so finally got my invoice emailed to me and the Fuging SERIAL NUMBER IS WRONG and that is not the one i PURCHASED,i made contact again and still no response from FNB !! I want the fuging correct invoice ASAP!!!!