Why some of the string variable not taking inputs from structure to void function?

In the below code some of the string is taking inputs but some are just skipping. I checked everything didn't discover anything. It would be ideal if you let me know where I am fouling up.I need to mention that I have a lot more work to do on this problem that's why I created functions

Expected Output

:::::::::::::::::::::::::: Choose Option From Below ::::::::::::::::::::::::::

1.for add new student

2.for add new teacher

3.for add new notice

1

Enter student's first name : Marry

Enter student's last name :lisa

Enter student's roll no :245

Enter student's section : C

Enter student's year :1

Enter student's semester :2

Enter student's department : IR

Enter student's email :lisa2@hotmail.com

Enter student's phone :15648955

Enter student's address : 2/A XYZ street

Output Now

:::::::::::::::::::::::::: Choose Option From Below ::::::::::::::::::::::::::

1.for add new student

2.for add new teacher

3.for add new notice

1

Enter student's first name :Enter student's last name :lisa

Enter student's roll no :245

Enter student's section :Enter student's year :1

Enter student's semester :2

Enter student's department :Enter student's email :lisa2@hotmail.com

Enter student's phone :15648955

Enter student's address :

Process returned 0 (0x0) execution time : 52.725 s Press any key to continue.

#include <iostream>
#include<string>
#include<iomanip>
using namespace std;

struct student{
string firstName;
string lastName;
int Roll;
string Section;
int Year;
int Semester;
string Department;
string Email;
int Phone;
string Address;
};

void student_part(void){
struct student stu;
cout<<"Enter student's first name :";
getline(cin,stu.firstName);
cout<<"Enter student's last name :";
getline(cin,stu.lastName);
cout<<"Enter student's roll no :";
cin>>stu.Roll;
cout<<"Enter student's section :";
getline(cin,stu.Section);
cout<<"Enter student's year :";
cin>>stu.Year;
cout<<"Enter student's semester :";
cin>>stu.Semester;
cout<<"Enter student's department :";
getline(cin,stu.Department);
cout<<"Enter student's email :";
getline(cin,stu.Email);
cout<<"Enter student's phone :";
cin>>stu.Phone;
cout<<"Enter student's address :";
getline(cin,stu.Address);

}



void add_info(void){
int choice;
cout<<"::::::::::::::::::::::::::"<<endl;
cout<<" Choose Option From Below"<<endl;
cout<<"::::::::::::::::::::::::::"<<endl;
cout<<"\n1.for add new student"<<endl;
cout<<"2.for add new teacher"<<endl;
cout<<"3.for add new notice"<<endl;
cin>>choice;
if(choice==1){
    student_part();
}


}


int main()
{
    add_info();

}