It's expected. It's pretty common actually.
Every round of COE bidding, there's bound to have some unused
bids.
Are you a first-time buyer? If not, please note that for
majority of the buyers, most of the prices of the cars come with
6 non-guaranteed bidding. That means, it is possible for you
to even wait up to 6 COE bidding rounds or 3 months in
equivalent, before you can secure your car.
Furthermore, for this current round, there are approximately 2
times as many bids placed as the quota set,... so if any
dealer has set a low COE rebate for you, chances are... he will not
bid this round and wait for the next round to secure your bid.
Afterall, only the highest bid within the quota wins.