diff --git a/pyrogram/crypto/mtproto.py b/pyrogram/crypto/mtproto.py
index dad30cd3..803db297 100644
--- a/pyrogram/crypto/mtproto.py
+++ b/pyrogram/crypto/mtproto.py
@@ -72,7 +72,7 @@ def unpack(b: BytesIO, session_id: bytes, auth_key: bytes, auth_key_id: bytes) -
         left = [[left[i:i + 8] for i in range(0, len(left), 8)] for left in left]
         left = "\n".join(" ".join(x for x in left) for left in left)
 
-        raise ValueError(f"Unknown constructor found: {hex(e.args[0])}\n{left}")
+        raise ValueError(f"The server sent an unknown constructor: {hex(e.args[0])}\n{left}")
 
     # https://core.telegram.org/mtproto/security_guidelines#checking-sha256-hash-value-of-msg-key
     # https://core.telegram.org/mtproto/security_guidelines#checking-message-length