variable ‘count’ set but not used in c

This is my palindrome code in c:

#include <stdio.h>
#include <stdlib.h>


char toUpperCase(char c) {
    if (c > 'Z') {
        c -= 32;
    }
    return c;
}

int isPalindrom(char word[40]) {
    int count = 0;
    int letterCount = 0;
    char lettersOnly[40];
    for (int i = 0; i < 40; i++) {
        char current = word[i];
        if (current == '\n' || current == '\0') {
            count = i;
            break;
        }
        
        if ((current >= 'A' && current <= 'Z') || (current >= 'a' && current <= 'z')) {
            lettersOnly[letterCount] = current;
            letterCount++;
        }
    }
   
    
   return 1;
}

It gives me an error that I set the variable "count" but didn't use it. I clearly used it tho.

How can I resolve this?

Your code only sets the value of count (count = i in the loop). It never reads this value, and thus it's safe to say that the program would have worked the same way had it been removed altogether.