Command Block Bug

I was building my server and entering coordinates in my command block and put the player as @p and it did not work, even tried it with my own name!

What I expected to happen was...:
To warp to the coordnaites
What actually happened was...:
I kept getting the same message in the command block and not tping!

Steps to Reproduce:
1. Place a command block
2. Enter coordniates
3. do @p as the player
4.It keeps throwing the same message in block (please speicfie the name of player)and does not tp to cords.