Called customer about service that was done yesterday. Customer had asked for estimates for scope of work that was to be done for system replacement or a fix. By the time I got on property it was about 530 and by the time I discovered the solution for the fix for the customer. The management had left and did not pick up their phone for me to communicate with them as to what I should do. I fixed the machine which only needed a fuse to be replaced. When I called today, the property manager started to yell at me without any explanation as to what happened the previous day. Place a do not service tag on this customer.