Blizzard is working on a fix for the Resplendent Sparks going missing for players on the Eternal realm.
Since the launch of Season 4, players have been reporting their previously collected sparks simply disappearing. Now we have word that a hotfix is coming today which will prevent the issue from affecting new players logging into S4 for the first time, and there will be an additional hotfix to address the players already affected.
The team is rolling out a hotfix this evening to put a stop gap on the issue for any new players that log into their accounts for Season 4 for the first time.
Separately, we are working on a fix to replenish missing sparks for users and will have more information on this in the coming days.
We apologize for the confusion and trouble with this. The team is actively working on this resolution ASAP.