Im new to linked list so can someone help me figure out why my program isn't printing as expected.

#include<iostream>
#include<fstream>  

using namespace std;  


//User struct
struct user 
{
	string f_name, l_name, address;
	string gender, phone;
	int id, age;
};

//Contact struct
struct contact
{
	int id;
	int contact_with;
	int contact_start;
	int contact_end;
	int distance ;
};
struct unode
{
	user data;
	unode *next;
	unode *prev;
};
struct ulist
{
	int size;
	unode *head;
	unode *tail;
}; 
struct cnode
{
	contact info;
	cnode *next;
	cnode *prev;
};
struct clist
{
	int size;
	cnode *head;
	cnode *tail;
}; 
//function to read the contacts.txt file
void contactfile(clist &chain)
{
		ifstream inptfile;
		inptfile.open("contacts.txt");
		while(inptfile.good())
		{
			cnode *node = new cnode;
			if (chain.head == NULL)
			{
				node->prev = NULL;
				node->next = NULL;
				chain.head = node;
				chain.tail = node;	
			}
			else
			{
				chain.tail->next = node;
				node->prev = chain.head;
				node->next = NULL;
				chain.tail = node;
			}
			
			inptfile>> node->info.id 
					>> node->info.contact_with 
					>> node->info.contact_start 
					>> node->info.contact_end 
					>> node->info.distance;
			chain.size++;
			
			string blankline;
			if(!getline(inptfile, blankline))
			break;
		}
	inptfile.close();
} 
//function to read the users.txt file
void userfile(ulist &list)
{ 

	//user_size = 0;
	ifstream infile;
	infile.open("users.txt");
		while(infile.good())
		{
			unode *node = new unode;
			if (list.head == NULL)
			{
				node->prev = NULL;
				node->next = NULL;
				list.head = node;
				list.tail = node;	
			}
			else
			{
				list.tail->next = node;
				node->prev = list.head;
				node->next = NULL;
				list.tail = node;
			}
			
			getline(infile, node->data.f_name);
			getline(infile, node->data.l_name);
			getline(infile, node->data.address);
			getline(infile, node->data.gender);
			infile>> node->data.id;
			infile>> node->data.age;
			infile>> node->data.phone;
			list.size++;
			
			string blankline;
			if(!getline(infile, blankline))
				break;
		}
	infile.close();
}

//function to print all users
void printusers(ulist &list)
{ 

	cout << "\t------------------------------------------------------------" << endl;
	cout << "\tUserID\tFname\tLname\tGender\tAge\tPhone\tAddress " << endl;
	cout << "\t------------------------------------------------------------" << endl;
	
		unode *node = list.head;
		for(int i = 0; i < list.size ;i++)
		{
				cout << node->data.f_name << endl;
				cout << node->data.l_name << endl;
				cout << node->data.address << endl;
				cout << node->data.gender << endl;
				cout << node->data.id << endl;
				cout << node->data.age << endl;
				cout << node->data.phone << endl;
				
            node = node->next; // select the next node*
		} 
	cout << "\tTotal users: "<< list.size <<endl;
	cout << "\t------------------------------------------------------------" << endl;

}

//function to print all contacts
void printcontacts(clist &chain)
{
	int duration;
	cout << "\t-------------------------------------------" << endl;
	cout << "\tUserID\tCon/With  Duration(s)  Distance(cm) " << endl;
	cout << "\t-------------------------------------------" << endl;
	cnode *node = chain.head;
		for(int i = 0; i < chain.size ;i++)
		{
		
		cout << node->info.id;
		cout<<	node->info.contact_with;
		cout<<	node->info.contact_start;
		cout<<	node->info.contact_end;
		cout<<	node->info.distance;
		
		node = node->next; // select the next node*
		}
	cout << "\tTotal contacts: " << chain.size <<endl; 
	cout << "\t-------------------------------------------" << endl;

}

//function to filter contacts.txt and print contacts who came into contact
void printcameintocontact(clist &chain) 
{
	int current_size;
	cout << "\t-------------------------------------------" << endl;
	cout << "\tUserID  Con/With  Duration(s) Distance(cm) " << endl;
	cout << "\t-------------------------------------------" << endl;
	cnode *node = chain.head;
		for(int i = 0; i < chain.size ;i++)
	{
		if ((node->info.contact_end - node->info.contact_start) >= 15 || node->info.distance < 100 )	
		{
		cout <<"\t"<< node->info.id << "\t " << node->info.contact_with << "\t    " <<
					  node->info.contact_end - node->info.contact_start << "\t\t" <<
					  node->info.distance  << endl;
					  current_size++;
		}
	}
	cout << "\tTotal contacts: " << current_size <<"/"<< chain.size <<endl; 
	cout << "\t-------------------------------------------" << endl;
	
}

//search user ID function
void searchbyid(ulist &list)
{
	int i, search;
	cout<<"\tenter the user ID to search: ";
	cin>> search;
	
		if (cin.fail()) //input validation
		{
			cout<<"\t---------------------"<<endl;
			cout<<"\t 0 User ID's found: "<<endl;
			cout<<"\t---------------------\n"<<endl;
			cin.clear(); //clears prvious input
			cin.ignore(20, '\n'); //discarding previous input
		}
	
	unode *node = list.head;
	for (i=0; i < list.size; i++)
	{
		if (search == node->data.id)
		{
			cout<<"\n\t-----------------------------"<<endl;
			cout<<"\tUserID:\t "<< node->data.id <<endl;
			cout<<"\tName:\t "<< node->data.f_name <<" "<< node->data.l_name << endl;
			cout<<"\tGender:\t "<< node->data.gender << endl;
			cout<<"\tAge:\t "<<node->data.age<<endl;
			cout<<"\tPhone:\t "<<node->data.phone <<endl;
			cout<<"\tAddress: "<<node->data.address<<endl;
			cout<<"\t-----------------------------\n"<<endl;
			break;
		}
		
	}
	
}

int main() 
{ 
	int opt;
	//Deaclare and initialize the list
	ulist list;
	list.head = NULL;
	list.tail = NULL;
	list.size = 0;
	
	clist chain;
	chain.head = NULL;
	chain.tail = NULL;
	chain.size = 0;
	
	userfile (list);
		//print startup message
		cout<<"\n\n\t\t*************************************************"<<endl; 
		cout<<"\n\t\tFIJI Ministry of health contact tracing analyser:"<<endl;
		cout<<"\n\t\t*************************************************"<<endl;
	
		cout<<"\n\t\tThis program analyses the data gathered by the  "<<endl;
		cout<<"\n\t\tFIJI ministry of health to help trace the possible "<<endl;
		cout<<"\n\t\tcontacts of the recent Covid-19 outbreak.\n"<<endl;
	
	system ("pause");
	system ("CLS"); 
	
	do{
		int opt;
		//print menu options
		cout<< "\n\tWhat would you like to do?"<< endl;
		cout<< "\n\t1. Exit the program "<< endl;
		cout<< "\t2. Print the users "<< endl;
		cout<< "\t3. Print all the contacts "<< endl;
		cout<< "\t4. Print the contacts who 'came into contact' "<< endl;
		cout<< "\t5. Search by user ID"<< endl;
	
		cout<< "\n\tEnter your option (1-5): ";
		//validating user input using a while loop
		while (!(cin>>opt) || opt > 5 || opt < 1)
		{
			cout<<"\n\tINVALID OPTION\n"<<endl;
			cin.clear();
			cin.ignore(20, '\n');
			break;
		}
		
		switch (opt){       
			case 1:          
				exit(1);          
				break;       
			case 2:          
				printusers(list);          
				break;  
	    	case 3:         
				printcontacts(chain);          
				break;       
			case 4:          
				printcameintocontact(chain); 
				break;
 			case 5:             
		 		searchbyid(list);          
				break;
			}
			
	
		
			system ("pause");
			system ("CLS");
	}while(opt != 1 );			 				

	
return 0; 
}