Question for THE KOREA CHAMBER OF COMMERCE INDUSTRY

We are importing goods from Korea, this is our first trial order. However, we have difficulty getting the Form AK (ASEAN - KOREA FTA)from seller for Import Duty exemption. Seller had taken nearly one month to-date to provide us (yet to get it). Is the Form difficult to be approved or the seller is not well verse on what to do? This makes us having second thought of importing - need clarification.