diff --git a/telethon/tl/custom/message.py b/telethon/tl/custom/message.py
index 019ab3f8..d7203a03 100644
--- a/telethon/tl/custom/message.py
+++ b/telethon/tl/custom/message.py
@@ -1080,7 +1080,8 @@ class Message(ChatGetter, SenderGetter, TLObject, abc.ABC):
         for row in self.reply_markup.rows:
             for button in row.buttons:
                 if isinstance(button, types.KeyboardButtonSwitchInline):
-                    if button.same_peer:
+                    # no via_bot_id means the bot sent the message itself (#1619)
+                    if button.same_peer or not self.via_bot_id:
                         bot = self.input_sender
                         if not bot:
                             raise ValueError('No input sender')