diff --git a/src/Client.Helpers.cs b/src/Client.Helpers.cs
index 25124ea..eefcd36 100644
--- a/src/Client.Helpers.cs
+++ b/src/Client.Helpers.cs
@@ -33,6 +33,7 @@ namespace WTelegram
 		/// <returns>an <see cref="InputFile"/> or <see cref="InputFileBig"/> than can be used in various requests</returns>
 		public async Task<InputFileBase> UploadFileAsync(Stream stream, string filename, ProgressCallback progress = null)
 		{
+			var client = await GetClientForDC(-_dcSession.DcID, true);
 			using (stream)
 			{
 				bool hasLength = stream.CanSeek;
@@ -65,9 +66,9 @@ namespace WTelegram
 						try
 						{
 							if (isBig)
-								await this.Upload_SaveBigFilePart(file_id, file_part, file_total_parts, bytes);
+								await client.Upload_SaveBigFilePart(file_id, file_part, file_total_parts, bytes);
 							else
-								await this.Upload_SaveFilePart(file_id, file_part, bytes);
+								await client.Upload_SaveFilePart(file_id, file_part, bytes);
 							lock (tasks) { transmitted += bytes.Length; tasks.Remove(file_part); }
 							progress?.Invoke(transmitted, length);
 						}
diff --git a/src/Client.cs b/src/Client.cs
index 2dc60d6..29d50b7 100644
--- a/src/Client.cs
+++ b/src/Client.cs
@@ -312,7 +312,7 @@ namespace WTelegram
 				try
 				{
 					Auth_ExportedAuthorization exported = null;
-					if (_session.UserId != 0 && IsMainDC && altSession.UserId != _session.UserId)
+					if (_session.UserId != 0 && IsMainDC && altSession.UserId != _session.UserId && altSession.DcID != _dcSession.DcID)
 						exported = await this.Auth_ExportAuthorization(Math.Abs(dcId));
 					await altSession.Client.ConnectAsync();
 					if (exported != null)
diff --git a/src/TL.Xtended.cs b/src/TL.Xtended.cs
index 7b36f1d..30a2c39 100644
--- a/src/TL.Xtended.cs
+++ b/src/TL.Xtended.cs
@@ -525,7 +525,7 @@ namespace TL
 	partial class Document
 	{
 		public override long ID => id;
-		public override string ToString() => Filename is string filename ? base.ToString() + ": " + filename : base.ToString();
+		public override string ToString() => $"{Filename ?? $"Document {mime_type}"} {size:N0} bytes";
 		public string Filename => GetAttribute<DocumentAttributeFilename>()?.file_name;
 		protected override InputDocument ToInputDocument() => new() { id = id, access_hash = access_hash, file_reference = file_reference };
 		public InputDocumentFileLocation ToFileLocation(PhotoSizeBase thumbSize = null) => new() { id = id, access_hash = access_hash, file_reference = file_reference, thumb_size = thumbSize?.Type };