I was able to get and set values of my custom form fields by using $form->getValue and $form->setValue in my previous issue here:
How to access / modify custom form fields valuesHow to access / modify custom form fields values
However, I am only able to use setValue and getValue in the function where the form was initialized. How do I make it such when I call the save function, I can access the form together with the custom fields I added during my loadForm() function?