/Setblock and /Fill is not contains "end_crystal"

Summary

The /Fill And /Setblock Does Not Contain "End_Crystal" command

Step to Reproduce

1. Use of chat and commands
2. Type via command 

   /fill <Position1> <Position2> end_crystal or /setblock <Position> end_crystal
   

Observed Result

The "End_Crystal" Is Not Have Contain in /Fill & /Setblock

Expected Behavior

/Fill & /Setblock should be Contains "End_Crystal"