Bug Report forhttps://neetcode.io/problems/longest-substring-without-duplicates

Please describe the bug below and include any steps to reproduce the bug or screenshots if possible.

in the problem , we are asked to get the length of a substring with no no repeating chars.
index starting form 1 for the length;
whereas in the third test case pwwkew, the solution should be 2 casue the third element 'w' is being repeated but the provided expected outcomes is given to be 3.

public int lengthOfLongestSubstring(String s) {
HashMap<Character,Integer> hash=new HashMap<>();
int index=0;
for( char ch:s.toCharArray()){
if(hash.containsKey(ch))return index;
else hash.put(ch,1);
index++;
}
return index-1;
}

the above is the copy of my solution.

If I’m mistaken, I’d appreciate it if you could point out where I went wrong so I can correct my understanding.