diff --git a/Resources/Protobufs/steamclient/friends.js.proto b/Resources/Protobufs/steamclient/friends.js.proto
index b14cea237..471c0a137 100644
--- a/Resources/Protobufs/steamclient/friends.js.proto
+++ b/Resources/Protobufs/steamclient/friends.js.proto
@@ -897,7 +897,7 @@ service ChatRoom {
 	rpc GetMyChatRoomGroups (.CChatRoom_GetMyChatRoomGroups_Request) returns (.CChatRoom_GetMyChatRoomGroups_Response);
 	rpc GetChatRoomGroupState (.CChatRoom_GetChatRoomGroupState_Request) returns (.CChatRoom_GetChatRoomGroupState_Response);
 	rpc GetChatRoomGroupSummary (.NotImplemented) returns (.CChatRoom_GetChatRoomGroupSummary_Response);
-	rpc AckChatMessage (.NotImplemented) returns (.NoResponse);
+	rpc AckChatMessage (.CChatRoom_AckChatMessage_Notification) returns (.NoResponse);
 	rpc CreateInviteLink (.CChatRoom_CreateInviteLink_Request) returns (.CChatRoom_CreateInviteLink_Response);
 	rpc GetInviteLinkInfo (.CChatRoom_GetInviteLinkInfo_Request) returns (.CChatRoom_GetInviteLinkInfo_Response);
 	rpc GetInviteInfo (.CChatRoom_GetInviteInfo_Request) returns (.CChatRoom_GetInviteInfo_Response);
diff --git a/SteamKit2/SteamKit2/Base/Generated/Unified/SteamMsgWebUIFriends.cs b/SteamKit2/SteamKit2/Base/Generated/Unified/SteamMsgWebUIFriends.cs
index 2b4635cc4..8ce889e3f 100644
--- a/SteamKit2/SteamKit2/Base/Generated/Unified/SteamMsgWebUIFriends.cs
+++ b/SteamKit2/SteamKit2/Base/Generated/Unified/SteamMsgWebUIFriends.cs
@@ -7637,7 +7637,7 @@ public interface IChatRoom
     CChatRoom_GetMyChatRoomGroups_Response GetMyChatRoomGroups(CChatRoom_GetMyChatRoomGroups_Request request);
     CChatRoom_GetChatRoomGroupState_Response GetChatRoomGroupState(CChatRoom_GetChatRoomGroupState_Request request);
     CChatRoom_GetChatRoomGroupSummary_Response GetChatRoomGroupSummary(NotImplemented request);
-    NoResponse AckChatMessage(NotImplemented request);
+    NoResponse AckChatMessage(CChatRoom_AckChatMessage_Notification request);
     CChatRoom_CreateInviteLink_Response CreateInviteLink(CChatRoom_CreateInviteLink_Request request);
     CChatRoom_GetInviteLinkInfo_Response GetInviteLinkInfo(CChatRoom_GetInviteLinkInfo_Request request);
     CChatRoom_GetInviteInfo_Response GetInviteInfo(CChatRoom_GetInviteInfo_Request request);