clickable sign is desplaying strange

clickable sign is desplaying strange

What I expected to happen was...:
that the command "/setblock ~ ~1 ~ minecraft:wall_sign 4 replace { Text1:"{ text:\"Game goal\", clickEvent:

{ action:run_command, value:\"/scoreboard players add @p sign 2\" }

}"}" would make a nice sign whit only "Game goal" on it like it used to in 1.8.

What actually happened was...:
It made a sign whit on the first line { text:"Game
and on the other lines was "null" displayed.

Steps to Reproduce: