DISRESPECTFUL Mc Donald manager screams and (****ing)

I had gone to order a large vanilla milkshake at the mc donalds in montclair and the day before i also ordered and they gave me a medium (wich i thought was a accident) so i informed the staff and manager about what happened just to make sure it doesn’t happen again because it is expensive and to waste money again is ridiculous so i told the manager he asked me “SO WHAT YOU WANT ME TO DO” and asked “DO YOU HAVE ANY PROOF” arrogantly, i told him no i don’t expect anything just please dont let it happen again and he walked off, i wait almost half a hour for my order and i ask what’s happening i get told they dont have any large cups only medium and small, so they give me 2 mediums (no problem) so i ask the lady please call you manager , he does not come i wait 15 minute and have to go call him myself as he doesn’t want to come , when he does come i told him here is the proof sir you were acting out as if i just want to get somthing out of it but i wasnt lieing about yesterday he start shout at me and going on with me infornt of all the other customers saying “WHAT YOU WANT ME TO DO?” I told him i don’t expect anything but in future you. Let you customer know. Instead of giving them less and letting them pay more. He carrys on shouting at me saying “WHAT YOU WANT ME TO DO “ i told him no sorry dont shout at me im speaking so nicely to you no reason to shout but he carrys on i told him no you will see what will happen , he says “okay show me” , so i go home and tell my father what had happened because honestly i work with people and you don’t disrespect a customer like this !!! my father isnt a man who would make issues but even he saw how bad this was , so we went back and he confronted the guy but when he asked for the manager and to speak to him he came to the front and then ran away , my father actually had to call him multiple times cause he was ignoring and running away?( how unprofessional) when he comes my father speaks to him asking why he had been so disrespectful he starts telling him what happened and the question stayed why were you disrespectful?!!!!!!! Why couldnt he just apologise for the mistake yesterday and explain why they disnt do what they did today and give us 2 mediums so we can get our moneys worth why dont you inform your customers?!!!! , i confront him again and he starts yelling over me i barely get a word out and i stop him because i hve had enough i told him please dont talk over me and told him i don’t expect anything free or want anything …and told him(how you spoke to me was unprofessional how can you talk to your customers like this as a manager it’s embarrassing) he sarcastically said “IM SO EMBARRASSED SORRY) and walked off . I left the restaurant at this point i will never recommend mc donalds to anyone and if this doesn’t get sorted some how i most definitely will be telling everyone i know about the disrespect mc donalds allows the standards have dropped very low i am so disappointed and i was such a supporter what has happened?!!!!