This article explains how to report spamming a channel on Telegram using an Android device.
Steps
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Step 1. Open the Telegram application on your Android device
The icon depicts a white paper airplane in a blue circle. It is located in the Applications menu.
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Step 2. Tap the channel you want to report
Find the channel you want to report in the conversation list and open it. This way you can view their chat in full screen.
If Telegram were to open a specific conversation, tap the arrow to go back and see the list of chats
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Step 3. Touch the icon that depicts three vertical dots
It is located at the top right of the conversation window and allows you to open a drop-down menu.
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Step 4. Select Report on the menu
A pop-up menu will appear from the bottom of the screen.
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Step 5. Tap Spam in the pop-up menu
The channel will be flagged for spam and the pop-up window will close.