Bot sends the same message again and again in a circle.

You may face this problem when you use forwarding from your account &1234567890 to a @destination channel without specifying the exact source channel (&1234567890#787878) and in the same time you join the @destination channel by your connected account.

Solution 1: set up forwarding from a specific channel using this format: &1234567890#787878.
Solution 2: leave the @destination channel.

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