问题 [数据包]在有function时提示Unknown function

[XS_Jiang]

为什么在有function时提示Unknown function？
我有一个自己写的数据包，在1.16.5JE服务端运行，有一个mc function，但是我/function时提示Unknown function，/reload过，/datapack list也有且已启用，为什么就是不能识别？

mcfunction:
say helloworld

cmd:
/datapack list
[20:41:48] [Server thread/INFO]: There are 2 data packs enabled: [vanilla (built-in)], [file/helloworld (world)]
[20:41:48] [Server thread/INFO]: There are no more data packs available
/function sdp:helloworld
[20:41:51] [Server thread/INFO]: Unknown function sdp:helloworld

树状图：
| pack.mcmeta
|
\---data
\---sdp
+---advancements
+---functions
| helloworld.mcfunction
| oversound.mcfunction
|
+---loot_tables
\---tags
\---functions