diff --git a/Signal/src/util/Pastelog.m b/Signal/src/util/Pastelog.m
index a4f602907..f5322086a 100644
--- a/Signal/src/util/Pastelog.m
+++ b/Signal/src/util/Pastelog.m
@@ -115,9 +115,14 @@ typedef void (^DebugLogUploadFailure)(DebugLogUploader *uploader, NSError *error
                     failWithError:OWSErrorWithCodeDescription(OWSErrorCodeDebugLogUploadFailed, @"Invalid response")];
                 return;
             }
+            
+            // Add a file extension to the upload's key.
             NSString *fileExtension = weakSelf.fileUrl.lastPathComponent.pathExtension;
             uploadKey = [uploadKey stringByAppendingPathExtension:fileExtension];
-            [weakSelf uploadFileWithUploadUrl:uploadUrl fields:fields uploadKey:uploadKey];
+            NSMutableDictionary *updatedFields = [fields mutableCopy];
+            updatedFields[@"key"] = uploadKey;
+            
+            [weakSelf uploadFileWithUploadUrl:uploadUrl fields:updatedFields uploadKey:uploadKey];
         }
         failure:^(NSURLSessionDataTask *_Nullable task, NSError *error) {
             DDLogError(@"%@ failed: %@", weakSelf.logTag, urlString);