C'mon guys, we're talking about cheap Chinese test equipment, typically purchased from Chinese marketplaces. Unless you're buying from Amazon or some established Western dealer, do you really expect warranty service at all, for any reason whatsoever? MAYBE you can get a damaged/DOA device replaced through the marketplace, if you're lucky. But getting service/support and a malfunctioning unit replaced later? Good luck.
And I say that as a Zoyi fan. I think they make pretty damn good gear in their price range. If it turns out they do provide timely support for such things, then I'll be an even bigger fan. But I have no real illusions about that.