Poor service

I was at Mcdonald's canal walk wanting to order a Mac feast deluxe meal and redeem the voucher with the free nuggets were me an my wife came to the counter to order they said to use the self service machine where we said we don't know how to redeem by the machine and they said it will show you how where we used the machine and it didn't want to redeem the machine kick us out and we asked to speak to the manager and they were up rupt with a person and said the machine not working and there nothing they can do and we ask for them to put I sign up to let people know and they said they can't do that the people must just see it not working I am disappointed in the service I got by McDonald's canal walk