Not getting the paid up letter

I have paid the full balance on my loan with direct axis and still account is not closed.

They have added this monthly interest on the 25th on a loan that was paid in full on the 20th December.

I have been requesting a paid up letter with no assistance for days now.

When I call the call centre I get transferred between legal and their call centre. Eventually I get zero assistance with poor service.

I have complained Vai their website and still no assistance