Jala's coffin (ref ID
0008636A) in Solitude catacombs is missing the persistent flag, while all coffins and burial urns dedicated to specific NPCs in the cell have it. I assume it may interfere from filling it with its owner inventory when this one dies.
Same statement for Endon's coffin (ref ID
000DEF6B) in Markarth Hall of the Dead.
I inspected Riften, Whiterun and Windhelm Halls of the Dead and there are no other similar issue to report.
I inspected 'Bring Out Your Dead' for the same concern and didn't find any error. However, there are many 'empty' urns that may suffer this issue if you later assign them to dedicated NPCs in the Winterhold Hall of the Dead.