I don't understand the test result

[oddure]

Tell us what’s happening:
I don’t understand why FreeCodeCamp says the result of this "1 eye for of 1 eye." should return False

function palindrome(str) {
//console.log(str)
let minuscula= str.toLowerCase()
//console.log(minuscula)
const flag=/[a-z]/g

let arr1= minuscula.match(flag) 

let word1="";
let word2="";

if(arr1== null){
  return true
} else{

  for(let i=0; i<arr1.length; i++){
    word1 += arr1[i]
  }

  console.log(word1)
  for(let i= arr1.length-1; i>=0; i--){
    word2 +=arr1[i]
  }
  console.log(word2)

  if(word1 === word2){
    return true
  }else{
    return false
  }

}

}


console.log(palindrome("1 eye for of 1 eye."))

Challenge: Palindrome Checker

Link to the challenge:

freeCodeCamp.org

[MatchaCrisp]

because" 1 eye for of 1 eye." is not a palindrome. With the punctuation and space removed, the string becomes: “1eyeforof1eye”, you can see the first 4 characters “1eye” should mean the end 4 characters are “eye1”, but it is not.

[oddure]

Thanks!! I find the error , the code was only looking for alphabetic character and not alphanumeric characters, without the numbers the sentence was palindrome “eyeforofeye”.