Double insurance payment

I received an email from MFC (Nedbank) requesting for proof of my insurance. I am insured at Nedbank and I send them this proof which is 4months old. They then came back and said that I need to provide proof not older than 3 months. I requested a confirmation letter from Nedbank, which I still haven't received. Now MFC threatens to take out further insurance on my behalf and add it to my monthly installment. Surely they can request this info from Nedbank?? They are both departments within Nedbank!