Hey, sorry to hear about this. Another user recently reported that items disappear too fast when they die.
Unfortunately, I am still trying to find out how to deal with this issue at all.
I do not manage anything regarding this mechanic. I used to have a plugin that would wipe stuff that laid around to much to prevent people from lagging the server by simply breaking lots of chests filled with cobblestone, but that plugin is not even installed at this point.
Even if this is an actual, repeatable issue, I would not know what setting or system to look into to change this behavior. I will continue to try to find something regarding this of course. If you can find someone online who has similar issues with recent Spigot builds or the current version of minecraft, please let me know.
On top of that, I have no way to trace back what you had when you died, so I cannot refund you (the FAQ has some post regarding this: https://uncovery.me/about-this-server/faq/?id=12#FAQ12). I only could refund people from the enderchest change because I can actually go back into the storage files for the old plugin and see what people had before we switched.
As the FAQ say, sorry, but no. Unless I have a logfile like for the inventory, I won’t. We had issues like this before and people were abusing it by telling me whatever they wanted and hoped I just hand it out to them.