diff --git a/Cargo.toml b/Cargo.toml
index 3afdc7f..9464129 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "dragonfly-api"
-version = "2.0.55"
+version = "2.0.56"
 authors = ["Gaius <gaius.qi@gmail.com>"]
 edition = "2021"
 license = "Apache-2.0"
diff --git a/proto/common.proto b/proto/common.proto
index dffa14f..d2ad2c8 100644
--- a/proto/common.proto
+++ b/proto/common.proto
@@ -350,7 +350,7 @@ message Range {
 // Piece represents information of piece.
 message Piece {
   // Piece number.
-  int32 number = 1;
+  uint32 number = 1;
   // Parent peer id.
   optional string parent_id = 2;
   // Piece offset.
diff --git a/src/common.v2.rs b/src/common.v2.rs
index cd7aa38..268861d 100644
--- a/src/common.v2.rs
+++ b/src/common.v2.rs
@@ -380,8 +380,8 @@ pub struct Range {
 #[derive(Clone, PartialEq, ::prost::Message)]
 pub struct Piece {
     /// Piece number.
-    #[prost(int32, tag = "1")]
-    pub number: i32,
+    #[prost(uint32, tag = "1")]
+    pub number: u32,
     /// Parent peer id.
     #[prost(string, optional, tag = "2")]
     pub parent_id: ::core::option::Option<::prost::alloc::string::String>,
diff --git a/src/descriptor.bin b/src/descriptor.bin
index e870c72..45c2423 100644
Binary files a/src/descriptor.bin and b/src/descriptor.bin differ