Faulty PC and "faulty" service!

I bought an Asus Vivobook from a very reputable company on 20.07.2022. Not even four months later my battery started dying within 90 minutes of being unplugged or due to load shedding. I teach online and this is my bread and butter!! Due to the warranty, Asus insisted I send my PC to them to test and the battery was ultimately replaced - a process that took nearly a month! Once again I'm faced with the same situation. Despite the best efforts of the company which sold me the Asus - many tests, texts, and calls to the supplier as well as Asus themselves - I've been told that it is now out of warranty and I should purchase an extended warranty to sort the matter out! Seriously?! Two batteries in less than 14 months. ASUS, your product is faulty!!!! Your service is appalling. Replace the battery or better yet replace the notebook!