Fgets() and sscanf() in a menu

Question

So, I'm having a problem with my code. I was trying to use fgets() for strings and scanf() for ints, but I read that this is bad practice and conflictive. I then tried using fgets() + sscanf() to read and parse a string to int. Still, for the love of me, I can't figure out what's happening! This is the code:

void menuUtente(CentroVacinacao *c)
{
    Utente u;
    char temp[20];

    printf("Introduza o nome do utente: \n");
    fgets(u.nomeUtente, NOME, stdin);
    while (getchar() != '\n')
    {
    }
    u.nomeUtente[strlen(u.nomeUtente) - 1] = '\0';
    printf("Introduza o número do utente: \n");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.numeroUtente);
    printf("Introduza a idade do utente: \n");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.idade);
    printf("Introduza o contacto do utente: \n");
    fgets(u.contacto, 9, stdin);
    u.contacto[strlen(u.contacto) - 1] = '\0';
    printf("Introduza a vacina tomada: \n");
    fgets(u.vacinaTomada.designacaoVacina, DESIGNACAO, stdin);
    u.vacinaTomada.designacaoVacina[strlen(u.vacinaTomada.designacaoVacina) - 1] = '\0';
    printf("Introduza as doses administradas: \n");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.dosesAdministradas);
    printf("Introduza a data da última dose (DD/MM/AAAA): \n");
    fgets(u.dataUltimaDose, 10, stdin);
    u.dataUltimaDose[strlen(u.dataUltimaDose) - 1] = '\0';

    acrescentaUtente(c, u);
}

And this is the output:

Can someone tell me what's happening? It's literally ignoring my first input and putting to inputs in the same line. Thanks in advance, been trying to figure this out for a while.

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

typedef struct sVaccine
{
    int vacID;
    char vacName[25];
    int numDoses;
    int monthsBetweenDoses;
} Vaccine;
typedef struct sPatient
{
    int patientNumber;
    char patientName[100];
    int age;
    char phoneNo[11];
    Vaccine vacTaken;
    int doses;
    char lastDoseDate[10];
} Patient;
typedef struct sVaccinationCenter
{
    int centerCode;
    char centerName[100];
    char address[20];
    Patient vaccinatedPatient[3000];
    Vaccine vaccineUsed;
    int numberOfPatients;
} VaccinationCenter;
VaccinationCenter init()
{
    VaccinationCenter c;
    c.numberOfPatients = 0;
    return c;
}
int addPatient(VaccinationCenter *c, Patient u)
{
    if (c->numberOfPatients == 3000)
    {
        return -1; // O centro está cheio
    }

    c->vaccinatedPatient[c->numberOfPatients] = u;
    c->numberOfPatients++;
    return 0;
}
void menuPatient(VaccinationCenter *c)
{
    Patient u;
    char temp[20];

    printf("Patient Name: ");
    fgets(u.patientName, 100, stdin);
    u.patientName[strlen(u.patientName) - 1] = '\0';
    printf("Patient Number: ");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.patientNumber);
    printf("Patient Age: ");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.age);
    printf("Patient Contact: ");
    fgets(u.phoneNo, 11, stdin);
    u.phoneNo[strlen(u.phoneNo) - 1] = '\0';
    printf("Vaccine Used: ");
    fgets(u.vacTaken.vacName, 25, stdin);
    u.vacTaken.vacName[strlen(u.vacTaken.vacName) - 1] = '\0';
    printf("Doses Taken: ");
    fgets(temp, sizeof(temp) - 1, stdin);
    sscanf(temp, "%d", &u.doses);
    printf("Last Dose Taken (DDMMAAAA): ");
    fgets(u.lastDoseDate, 10, stdin);
    u.lastDoseDate[strlen(u.lastDoseDate) - 1] = '\0';

    addPatient(c, u);
}
void listCenter(VaccinationCenter c)
{
    for (int i = 0; i < c.numberOfPatients; i++)
    {
        printf("Patient Name: %s\n", c.vaccinatedPatient[i].patientName);
        printf("Patient Number: %d\n", c.vaccinatedPatient[i].patientNumber);
        printf("Patient Age: %d\n", c.vaccinatedPatient[i].age);
        printf("Patient Contact: %s\n", c.vaccinatedPatient[i].phoneNo);
        printf("Vaccine Used: %s\n", c.vaccinatedPatient[i].vacTaken.vacName);
        printf("Doses Taken: %d\n", c.vaccinatedPatient[i].doses);
        printf("Last Dose Taken: %s\n", c.vaccinatedPatient[i].lastDoseDate);
    }
}
int main(int argc, char const *argv[])
{
    VaccinationCenter c = init();
    int opcao = -1;

    //menuUtente(&c);
    c.numberOfPatients = 0;

    while (opcao != 0)
    {
        printf("1 - Insert patient;\n");
        printf("2 - List patients;\n");
        printf("0 - Leave;\n");
        printf("Enter your choice -> ");
        scanf("%d", &opcao);
        switch (opcao)
        {
        case 1:
            menuPatient(&c);
            break;
        case 2:
            listCenter(c);
            break;
        case 0:
            break;
        default:
            printf("Invalid Option!\n");
            break;
        }
    }
    return 0;
}

Answer 1

Try adding this getchar():

printf("Enter your choice -> ");
scanf("%d", &opcao);
getchar();

This seemed to make the second part of code you pasted work. It doesn't skip anymore and it lists the registered patients. The thing is: I couldn't understand if thats the issue you are trying to solve.