Device not working accordingly and huge let down in service

Good day

I purchased the RCT 1000VA Line Interactive Uninterruptible Power Supply for R2000 and I was concerned with the time that it last when using it, I bought it because I'm working from home and thought it will help me with using it with my work computer.

I called a 4days after receiving it and the lady I spoke too said she will escalate and find out more information about it as it only lasts for less than an hour when using it. It's been 2weeks I have this device. Never got any feed back untill I called back on the 29th July 2021 again and the guy told me it only last for 15min.I cannot buy a power supply for me to work for R2000 and I can only use it for 15minutes.The agent by the name of Apile which is the last agent I spoke too said there is nothing they can do because I already used the device.Asked to speak to a manager and said he will call, still waiting for the call even now.whote an email to their sow called complaint and Yonela Peter rep**** and said if I'm not happy with the product I should return it within 14days and only if it's unused. I can't get help from homechoice and I'm stuck with a power supply for R2000 that is not working for me.