platform-ststm32: Code appears to upload but does not run on STM32 Nucleo L476RG

I recently updated VScode on my mac and since then any code upload onto my Nucleo L476RG appears to upload (the indicator light flashes red and green when uploading), but the code doesn’t run; anything I try to output to the serial port doesn’t show up, and a test code I created to blink the built-in LED doesn’t work either. I’ve tried changing the upload protocol, reverting back to the old version of VScode, even reverting back to an older version of the C++ extension on VScode, but nothing works. My friend can run everything exactly the same on a PC with no issues, which makes me think this is a mac problem; I’m just not sure what went wrong.

Test code:

// Start program

#include <Arduino.h>
#include <PrintStream.h>

void setup() 
{
    pinMode(LED_BUILTIN,OUTPUT);
    digitalWrite(LED_BUILTIN,HIGH);

    // Open serial port
    Serial.begin(115200);
    //Wait for connection to be set up
    delay(1000);

    // Intro Output
    uint16_t class_num = 507;
    Serial << endl << "Starting Program";
    Serial << endl << "Class: ME " << class_num << endl;


    pinMode(LED_BUILTIN,OUTPUT);
    digitalWrite(LED_BUILTIN,HIGH);
}

void loop() 
{
    Serial.print(" - "); 

    digitalWrite(LED_BUILTIN,HIGH);
    delay(1000);
    digitalWrite(LED_BUILTIN,LOW);
    delay(1000);
}

Platformio.ini:

; PlatformIO Project Configuration File
;
;   Build options: build flags, source filter
;   Upload options: custom upload port, speed and extra flags
;   Library options: dependencies, extra library storages
;   Advanced options: extra scripting
;
; Please visit documentation for the other options and examples
; https://docs.platformio.org/page/projectconf.html

[env:nucleo_l476rg]
platform = ststm32
board = nucleo_l476rg
framework = arduino

;bits per second from mC to computer to make sure they are the same frequency- otherwise file downloads will not work
monitor_speed = 115200

upload_protocol = stlink