Why is my iPhone 16 Pro Max's battery draining faster after updating to iOS 18.3.2?

Hello. I have an iPhone 16 Pro Max. Recently, I updated it to iOS 18.3.2, and I noticed that the battery doesn’t last as long as before. I don’t use my phone for heavy tasks; I only use it for communication. Compared to the previous update, I’ve also noticed that my phone gets slightly warmer.

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