Worst service ever from Vital Aire

Worst service ever!! They never have stock of anything, they only have 2 sizes nasal canulas, a neonatal and a HUGE adult one, not all adults have such huge nostrils and it suffocates you!!!! I had to wait 2 days for a replacement machine and my oxygen cylinder was finished, after eventually receiving the new machine with a very grumpy attitude from staff member I had to wat anoyher week and a half for the humidifier bottle for the machine!!! There is a no care attitude, promises made and not kept! I have complained to the customercare no, that ocationally works and my problem was supposed to have been escalated but it never happened. Why is there allways a stock problem and when they do have stock why is it so much trouble for the representitives to deliver and why do I jave to wait so long ? It is absolutely radiculous!!!