Unacceptable Service

Hi there. I have a mum that needs oxygen 17 hours a day. And if she doesn't get it she is unable to breath. I have been trying to get someone to come out to my mum to service or replace this machine because it firstly does not sound normal it makes a noise that was not there. My mums nose started bleed so bad that i had to rush her to the dr. And was told that the air from this machine is too dry and causing this. I called Vital Aire like the 4th time for this year. My last reference number is ***4. And i insisted that the call me 1st before they come out mainly because i want to be there and that we need to make sure there is not load shedding so the machine can be tested. The person arrives on Thursday the 3rd. Didn't call me and it was load shedding. So he was unable to test the machine. He promised he will return. Today is Tuesday and still nothing. This service is unacceptable mainly because it is a medical issue and my mum 's wellbeing depends on this. Thank