Searching using Ifstream

I've been recently trying to write a contacts list
but I keep facing some problems (sorry for poor english btw)
here's my code:

class contact{
private:
  std::string name;
  long int number;
public:
  void append();
  void search();
};

void contact::append(){
    std::cin.ignore();
    std::ofstream cnt;
    cnt.open("contacts.dat", std::ofstream::app);
    std::cout<<"Please enter the name\n";
    std::getline(std::cin, name);
    cnt << "Name: " << name << std::endl;
    
    bool flag=true;
    while(flag){
    std::cout<< "Enter the number:\n";
    std::cin >> number;
    if(std::cin.good()){
    try{
      if(number == 0){
    throw number;
      }
      else{
    cnt << "number: +98" << number <<"\n\n";
    flag=false;
    break;
      }
    }
    catch (...){
      std::cout<<"Unvalid entry\n\a";
    }
    }
    else{
      std::cout<<"unvalid entry, please enter an integer\a"<<std::endl;
      std::cin.clear();
      std::cin.ignore(10000, '\n');
    }
    }
    std::cout<<"Added Successfully";
      cnt.close();
}

void contact::search(){
  std::cin.ignore();
  std::ifstream sr;
  sr.open("contacts.dat");
  std::string search_name;
  bool found = false;
  std::cout<<"Enter a name for finding its phone number\n";
  std::getline(std::cin, search_name);
  while(sr>>number){
    sr>>name;
    if(name == search_name){
      std::cout<<"Name: "<<name<<std::endl;
      std::cout<<"Number: "<<number<<std::endl;
      found=true;
      break;
    }
  }
 if (found==false){
    std::cout<<search_name<<" not found";
  }
  sr.close();
}

int main(){
  contact cont;
  int choice;
     while (1) {
    std::cout << "Enter Your Choice\n";
    std::cout << "\t1. Add contact \n";
    std::cout << "\t2. Find contacts \n";
    std::cin >> choice;

    switch(choice){
    case 1:
      cont.append();
      break;
    case 2:{
      cont.search();
      }
    default:
      std::cout<<"\ninvalid Choice\n\a";
    }
     }
}

I already added some contacts to contacts.dat via the program.

contacts.dat:

Name: john
Number: +98911111111
Name: joe
Number: +98914523525
Name: example
Number: +98954645236

but when I try to run the code:

Enter Your Choice
        1. Add contact
        2. Display Contacts
2
Enter a name for finding its phone number
john
john not found