Let's verify what model of iPhone you actually have. Please post the model that appears on your phone. Here's a couple of ways to find it.
Look in Settings
Go to Settings > General > About. To the right of Model, you'll see the part number. To see the model number, tap the part number.
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Look on your device
On an iPhone 7 or earlier, an iPad, or an iPod touch, find the model number on the back of your device.
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