Guild Wars 2

Bonus Chest 1 spawned but the dragon chest ones did not. this was AFTER reset so it wasnt that i had already done it before.

Bonus Chests can only be earned once per day, per account and those are tied to the Daily Reset.

However, I believe Zone Boss Chests reset on a 24 hour schedule from when it was last looted (as you can get the Boss Chest once per day on each character you have) and is not tied to the Daily Reset timer like the Bonus Chest is. If this is the case, then it is likely that it had not been 24 hours since you last looted the Boss Chest for that event on that character and that is why it did not appear for you.

https://forum-en.gw2archive.eu/forum/info/news/Upcoming-mega-boss-chest-change/1656442

I’ve only ever been able to find an Anet dev stating “per day” and not “per 24-hour period” or “per daily reset period”. I still, to this day, am confused on their definition of “per day” in regards to boss chests. Sorry I cannot be more certain of how it works. Even the Wiki is vague and does not offer exact definitions of what “per day” or “normal amount of time” actually mean.