How to debug matrix keyboard scanning?

My problem is nothing is display to my LCD when * is pressed. There are no errors in my code, but when I run it and press the * to enter set mode and update the time and temp, nothing is happening.

For my project, when the * is pressed, the code is supposed to enter set mode. And in set mode, you are supposed to enter the hour, minute, seconds, am/pm, and temperature from sensor. After that, everything is supposed to update and show everything at the end. That isn't what is going on when I run the code. I have a nucleo board and am sure I have everything correctly wired. Just need help with my code that is provided.

#include <iostream>
#include <string>
#include "mbed.h"
#include "TextLCD.h"

// Define the keypad layout
char key_map[4][4] = {
    {'1', '2', '3', 'A'}, //1st row
    {'4', '5', '6', 'B'}, //2nd row
    {'7', '8', '9', 'C'}, //3rd row
    {'*', '0', '#', 'D'} //4th row
};

// Define the GPIO pins connected to the keypad
#define ROW1_PIN PA_6
#define ROW2_PIN PA_7
#define ROW3_PIN PB_6
#define ROW4_PIN PC_7
#define COL1_PIN PA_9
#define COL2_PIN PA_8
#define COL3_PIN PB_10
#define COL4_PIN PB_4

// Define the GPIO pins connected to the LCD
#define RS_PIN PB_5
#define E_PIN PB_4
#define D4_PIN PC_7
#define D5_PIN PB_6
#define D6_PIN PA_7
#define D7_PIN PA_6

// Function prototypes
void initialize_gpio();
void set_row(int row);
void reset_rows();
char keypad_scan();
int col_scan();
void update_time_lcd();
void set_mode();
void update_temperature_lcd();

// Global variables for GPIO pins
DigitalOut ROW1(ROW1_PIN);
DigitalOut ROW2(ROW2_PIN);
DigitalOut ROW3(ROW3_PIN);
DigitalOut ROW4(ROW4_PIN);
DigitalIn COL1(COL1_PIN, PullUp);
DigitalIn COL2(COL2_PIN, PullUp);
DigitalIn COL3(COL3_PIN, PullUp);
DigitalIn COL4(COL4_PIN, PullUp);
TextLCD lcd(RS_PIN, E_PIN, D4_PIN, D5_PIN, D6_PIN, D7_PIN);

int main() {
    initialize_gpio();

    std::string sequence;

    while (true) {
        char key = keypad_scan();
        sequence += key;

        std::cout << sequence;

        if (key == '*') {
            set_mode(); // Enter Set Mode when * is pressed
        }
    }

    return 0;
}

void initialize_gpio() {
    ROW1 = ROW2 = ROW3 = ROW4 = 1;
}

void set_row(int row) {
    switch (row) {
        case 0:
            ROW1 = 0; ROW2 = 1; ROW3 = 1; ROW4 = 1;
            break;
        case 1:
            ROW1 = 1; ROW2 = 0; ROW3 = 1; ROW4 = 1;
            break;
        case 2:
            ROW1 = 1; ROW2 = 1; ROW3 = 0; ROW4 = 1;
            break;
        case 3:
            ROW1 = 1; ROW2 = 1; ROW3 = 1; ROW4 = 0;
            break;
    }
}

void reset_rows() {
    ROW1 = ROW2 = ROW3 = ROW4 = 1;
}

char keypad_scan() {
    char key_pressed = '\0';

    for (int row = 0; row < 4; ++row) {
        set_row(row);

        int col = col_scan();
        if (col != -1) {
            key_pressed = key_map[row][col];
            break;
        }
    }

    reset_rows();
    return key_pressed;
}

int col_scan() {
    if (!COL1) return 0;
    if (!COL2) return 1;
    if (!COL3) return 2;
    if (!COL4) return 3;
    return -1;
}

void update_time_lcd() {
}

void set_mode() {
    // Prompt user to set hour
    lcd.cls();
    lcd.printf("HOUR");
    int hour = 0;
    while (true) {
        char key = keypad_scan();
        if (key >= '0' && key <= '9') {
            hour = hour * 10 + (key - '0');
            lcd.printf("%d", hour);
        } else if (key == '#') {
            if (hour >= 1 && hour <= 12) {
                break;
            } else {
                lcd.cls();
                lcd.printf("ERROR");
                lcd.cls();
                lcd.printf("HOUR");
                hour = 0;
            }
        }
    }

    // Prompt user to set minute
    lcd.cls();
    lcd.printf("MIN");
    int minute = 0;
    while (true) {
        char key = keypad_scan();
        if (key >= '0' && key <= '9') {
            minute = minute * 10 + (key - '0');
            lcd.printf("%d", minute);
        } else if (key == '#') {
            if (minute >= 0 && minute <= 59) {
                break;
            } else {
                lcd.cls();
                lcd.printf("ERROR");
                lcd.cls();
                lcd.printf("MIN");
                minute = 0;
            }
        }
    }

    // Prompt user to set seconds
    lcd.cls();
    lcd.printf("SEC");
    int second = 0;
    while (true) {
        char key = keypad_scan();
        if (key >= '0' && key <= '9') {
            second = second * 10 + (key - '0');
            lcd.printf("%d", second);
        } else if (key == '#') {
            if (second >= 0 && second <= 59) {
                break;
            } else {
                lcd.cls();
                lcd.printf("ERROR");
                lcd.cls();
                lcd.printf("SEC");
                second = 0;
            }
        }
    }

    // Prompt user to set temperature
    lcd.cls();
    lcd.printf("TEMP");
    float temperature = 0.0f;
    while (true) {
        char key = keypad_scan();
        if (key >= '0' && key <= '9') {
            temperature = temperature * 10 + (key - '0');
            lcd.printf("%.2f", temperature);
        } else if (key == '#') {
            // Temperature set
            break;
        }
    }
}