Cheap Chinese crap people. These things die early deaths more than people here care to admit.
For me, I had a Coolfire 4 die withing a week and the replacement died a month later with only a weeks worth of vaping. I've had 10 out of 10 evods leak severely. I sticks that fail to fire every 10th draw.
Oh I could go on at even greater length but I won't. This market is flooded with crap that has a shiny paint job.
You can contact "innokin paul" directly threw Reddit. He's handled a number of other innokin failures and they seem to take a personal interest in their products success.
One of the secrets is to know how to contact a company for the best results. I've used FB to send messages when I haven't gotten results from email that they list.
Eleaf is another issue. They left vendors high and dry when problems with the istick started showing up. That's a lot of bad pr and I'll always be cautious about owning another one of their devices. That is unusual. Many companies wouldn't survive that. Clouper ran into similar troubles but tried to make things right.
Aspire and Kanger include warrenties with their dealer contracts. They expect customers to return items directly to the vendor for replacement and the vendor returns faulty products back to them. It's hard to get them to do anything outside of that format unless you buy directly from them on their website, then that retail division is treated like another vendor.
Eleaf went to a similar system, or has tried to, buy not accepting returns unless bought direct through them but they didn't have a contract with vendors. Now I think their return requirements were modified again. They are strict. Need to check.
Manufacturers are responsive to customer demands and if people don't demand warrenties, they won't be provided. Sigelei used to have a year warrenty with US repair, in or out of warrenty but no one seemed that interested so it was dropped. That is a reason why a lot of people buy provari, including me, because they offer service. It costs money.