Passing Values to Functions with Arguments, make it right

Is there a bug one this “level”, I only got two marks green first and last. It should be the first two…

Your code so far

// Example
function ourFunctionWithArgs(a, b) {
  console.log(a - b);
ourFunctionWithArgs(10, 5); // Outputs 5

// Only change code below this line.

function functionWithArgs(one, two) {
  console.log(one + two);


Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; rv:61.0) Gecko/20100101 Firefox/61.0.

Link to the challenge:

As far as I can tell that code should be correct. I wonder if there is a bug…? The browser console shows the correct answer.