It seems that a selected number of iPhone 6S and iPhone 6S Plus has been affected by what appears to be a very specific power issue. As such, Apple has announced a free repair program that's provided worldwide, including Malaysia.
As it turns out, certain iPhone 6S series devices may not power on due to a component failure, and it affects certain devices within a limited serial number range for those manufactured between October 2018 to August 2019. If you think you're one of those who might be affected, you can check Apple's official website and key in your device's serial number.
If your device has been confirmed to be listed, you can send it to the nearest Apple authorised service provider to get it fixed and settled. Before sending it in though, be sure to backup your iPhone to iTunes or iCloud.
But what if you've paid to have it fixed already? Apple states that any iPhone 6s or iPhone 6s Plus that was affected by this issue and had paid to repair their device, they can contact Apple about a refund.