I am facing memory leak problem with the below code

```
static char **edits1(char *word)
{
    int next_idx;
    char **array = malloc(edits1_rows(word) * sizeof (char *));
    if (!array)
        return NULL;

    next_idx = deletion(word, array, 0);
    next_idx += transposition(word, array, next_idx);
    next_idx += alteration(word, array, next_idx);
    insertion(word, array, next_idx);

    return array;
}

static void array_cleanup(char **array, int rows) {

        int i;

        for (i = 0; i < rows; i++)
            free(array[i]);
}

static char *correct(char *word,int *count) {

        char **e1, **e2, *e1_word, *e2_word, *res_word = word;
        int e1_rows, e2_rows,max_size;

        e1_rows = edits1_rows(word);
        if (e1_rows) {
            e1 = edits1(word);
        *count=(*count)*300;
            e1_word = max(e1, e1_rows,*count);

            if (e1_word) {

                array_cleanup(e1, e1_rows);
                        free(e1);
                return e1_word;

            }
        }

    *count=(*count)/300;

    if((*count>5000)||(strlen(word)<=4))
        return res_word;

        e2 = known_edits2(e1, e1_rows, &e2_rows);
        if (e2_rows) {
        *count=(*count)*3000;
            e2_word = max(e2, e2_rows,*count);
            if (e2_word)
                    res_word = e2_word;
        }

        array_cleanup(e1, e1_rows);
        array_cleanup(e2, e2_rows);

        free(e1);
        free(e2);
        return res_word;
}

```

I don’t know why `free()` is not working. I am calling this function "correct" in thread, multiple threads are running simultaneously.I am using Ubuntu OS.