This article explains how to update the phone number on Telegram using an Android device.
Steps
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Step 1. Open Telegram
It's the icon of a white paper airplane on a blue background. It is located in the app drawer.
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Step 2. Tap ☰
It is located in the upper left.
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Step 3. Tap Settings
It's almost at the bottom of the menu.
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Step 4. Tap your current phone number
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Step 5. Tap Change number
A pop-up window will appear to notify you that the new phone number will also be updated in your contacts address book.
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Step 6. Tap OK
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Step 7. Enter the new number and tap
Telegram will send you a text message containing an activation code.
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Step 8. Enter the code and tap
The phone number will be updated on Telegram.