Problem running switch case + Serial, maybe because of classes

Hello. I’ve been trying to run a program which basically uses two switch case functions: one of them reads the serial port and changes a variable accordingly, and the other switches between functions regarding that variable. I had my code written in plain C but I wanted to try making it into C++ because it gets long and hard to browse. I think the creation of my main class is mostly done, but I cannot seem to find my way through the serial object and I think the problem might be there. Basically I cannot switch, my function is not working. I will paste the github link here, any help is greatly appreciated.