at the moment, the PoS difficulty is extremely high due to some user wallets with supper old coins that haven't staked for a year or two because the wallet didin't have the function to unlock to stake.
you can see it on the explorer at http://bcf.altcoinwarz.com

The unlock to stake function was just added/fixed recently - so there is a large backlog of staking going on.

The staking difficulty is affected by age, and amount - so we have to wait until the old farts get done staking before we get our chance.
(or there is something wrong with the difficulty adjustments - i will be looking into that soon)