We can definitely take a closer look into why the battery in your iPhone 6 is draining so quickly. Over time, the rechargeable batteries in all iPhone models will diminish in their capacity and peak performance and will eventually need to be replaced. For iPhone 6 and later, iOS 11.3 and later added new features to show battery health and recommend if a battery needs to be replaced. These can be found in Settings > Battery > Battery Health. Please follow those steps to Check your Battery Health. Let us know if you have any further questions or concerns.
Sean, AT&T Community Specialist
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