For whatever reason, the buds blasted. That typically happens if the plant is stressed, or there's a change in conditions. If the leaves and roots look good, then you should be fine.
I received a flowering Phal in the mail and it blasted all of its blooms en route to me. I figured the plant looked healthy enough to try again, so I cut the spike to encourage it to grow more buds. You can do this with Phals.
I don't usually bother after their normal blooming, because I'd rather the plant put its energy into growing for next season. But if it didn't even bloom through its first time, what the heck...it should have enough energy to try again.
If you'd like to try this, notice on the spike the nodes or bracts that run up from the base - sort of like joints spaced every few inches. There are usually several non-blooming nodes, before the first node that supported a bud. Cut the spike above the highest non-blooming node and below the first bud node. Then wait a couple of weeks, and the spike should put out a new branch, which will develop new buds.