Iam getting erroe as dont change below the line?

Tell us what’s happening:

Your code so far

// Setup
var a ;
var b;

// Only change code below this line

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36.

Link to the challenge:

Why have you changed the code above the comment line? It says:

// Only change code below this line

Just reset the code and stick to the instructions.