Почему не работает функция Choose_Travelers?

#include<iostream>
using namespace std;
 
 
struct Travelers
{
    int ticket_code;
    string lastname;
    int numberofthings;
    int luggage_weight;
    Travelers* Next;
};
 
Travelers* Head = 0;
struct Date {
    int day;
    int month;
    int year;
};
Date* Head2 = 0;
void Insert_Traveler(Travelers** list, Travelers* t, unsigned int pos)
{
    if (pos == 0) {
        t->Next = *list;
        *list = t;
    }
    else {
        Travelers* p = *list;
        for (unsigned int i = 0; p->Next; i++, p = p->Next)
            if (i == pos - 1)
                break;
        t->Next = p->Next;
        p->Next = t;
    }
}
Travelers* Choose_Travelers(Travelers* list, unsigned int pos) 
{ 
    Travelers* p = list;       
    for (unsigned int n = 0; p; n++, p = p->Next) { 
        if (n == pos) 
            break; 
    }      
    return p; 
}
Travelers* Choose_NextAndBefore1(Travelers* list, unsigned int pos) {
    Travelers* p = list;
    for (unsigned int n = 0; p; n++, p = p->Next) {
        if (n == pos)
            break;
    }
    return p + 1;
}
Travelers* Choose_NextAndBefore2(Travelers* list, unsigned int pos) {
    Travelers* p = list;
    for (unsigned int n = 0; p; n++, p = p->Next) {
        if (n == pos)
            break;
    }
    return p - 1;
}
int Location(Travelers* list, string key){
    Travelers* p = list;
    unsigned int n = 0;
    for (; p; n++, p = p->Next) {
        if (p->lastname == key) {
        }
    }
    return n;
}
Travelers* Delete_Traveler(Travelers** list, unsigned int pos)
{
    Travelers* d = 0;
 
    if (pos == 0) {
        d = *list;
        *list = d->Next;
    }
    else {
        Travelers* p = *list;
        for (unsigned int i = 0; p->Next; i++, p = p->Next)
            if (i == pos - 1) {
                d = p->Next;
                p->Next = d->Next;
                break;
            }
    }
 
    return d;
}
 
void Print_Travelers(Travelers* list)
{
    for (Travelers* p = list; p; p = p->Next)
        cout << "code: " << p->ticket_code
        << "  " << p->lastname
        << " nth: " << p->numberofthings
        << " weight: " << p->luggage_weight
        << '\n';
    cout << '\n';
}
 
 
int main()
{
    for (int i = 0; i < 10; i++) {
        char nm[10];
        Travelers* p = new Travelers;
        p->ticket_code = rand() % 1000;
        sprintf_s(nm, "tr_%d", i);
        p->lastname = nm;
        p->numberofthings = rand() % 5 + 1;
        p->luggage_weight = (rand() % 10 + 1) * p->numberofthings;
 
        Insert_Traveler(&Head, p, i);
    }
 
    cout << "list of travelers\n";
    Print_Travelers(Head);
 
    cout << "delete some travelers\n";
    Travelers* p = Delete_Traveler(&Head, 9);
    if (p) {
        cout << "delete as pos " << 9 << "  "
            << "code: " << p->ticket_code
            << "  " << p->lastname
            << " nth: " << p->numberofthings
            << " weight: " << p->luggage_weight
            << '\n';
        delete p;
    }
 
 
    for (int i = 0; i < 10; i++) {
        p = Delete_Traveler(&Head, i);
        if (p) {
            cout << "delete as pos " << i << "  "
                << "code: " << p->ticket_code
                << "  " << p->lastname
                << " nth: " << p->numberofthings
                << " weight: " << p->luggage_weight
                << '\n';
            delete p;
        }
    }
 
    cout << "------\n";
    cout << "\nlist of travelers after deletions\n";
    Print_Travelers(Head);
    int pos;
    cout << "Choose index"<<endl;
    cin >> pos;
    Travelers* t = Choose_Travelers(Head, pos);
    cout << "Enter a key you want to choose" << endl;
    string key;
    cin >> key;
    int k=Location(Head, key);
}

int Location(Travelers* list, string key){
    Travelers* p = list;
    unsigned int n = 0;
    for (; p; n++, p = p->Next) {
        if (p->lastname == key) break; // была ошибка
    }
    return n; // если не найдет вернет конец 
}

        sprintf_s(nm, "tr_%d", i);
        p->lastname = nm;

int Location(Travelers* list, string key){
    Travelers* p = list;
    unsigned int n = 1;
    for (; p; n++, p = p->Next) {
        if (p->lastname == key) break;
    }
    if (p== NULL) return 0;
    return n;
}