Computer Mania running away from taking responsibility for their devices.

I bought a GIZZU ups and in just under a year it stopped working, when I took them back they replaced it. Guess what, the new one also died within 6 months.

When I took it back, they said the new one's warranty was under the old one, so since that warranty has finished a year, it means the new one also is no longer covered, so we can't help you.

My argument with the warranty /repairs manager is that I don't want to change your warranty policy, but it's my first time hearing this, at least I deserve to have known this before I took the second device and no one explained anything to me. All along I was under the impression that it's new and has it's own warranty, hence I took it back.

He is ghosting me, I have a faulty device I don't know what to do with and should load shedding hits I will be in trouble as I work from home full time.

Please help if you know how to deal with this.