There's a pretty gnarly bug with Dimension 17 that resets all your spent ascension shards, including Infinite shards and D shards. D shards can be retrieved with annihilation, but the infinite shards have to be grinded out again, which sucks at high level.
Seems to happen when you change dimensions to or from 17, tho it doesn't happen every time. I recommend backing up your save (export) before anyone ventures there, just in case.