Looking at the price level at ccedk you seem to be a little bit to low with your offer.

The best NBT sell (= BKS buy) offer is at 4.25 NBT (0.235 BKS per NBT).
If you try to get BKS from the BKS sell side, you have to pay 4.34 NBT (0.23 BKS per NBT).

I expect the price level to rise, because the BKS sale from BCE has been ended - but you are aware of that
...and I hope for the trading pair to get flipped soon - this notation really makes the brain hurt