diff --git a/app/services/api/v1/issues/update_service.rb b/app/services/api/v1/issues/update_service.rb
index 9d2e01924..594200286 100644
--- a/app/services/api/v1/issues/update_service.rb
+++ b/app/services/api/v1/issues/update_service.rb
@@ -72,11 +72,11 @@ class Api::V1::Issues::UpdateService < ApplicationService
       @updated_issue.attachments = @attachments || Attachment.none unless attachment_ids.nil?
       @updated_issue.issue_tags_relates.destroy_all & @updated_issue.issue_tags = @issue_tags || IssueTag.none unless issue_tag_ids.nil?
       @updated_issue.issue_tags_value = @issue_tags.order("id asc").pluck(:id).join(",") unless issue_tag_ids.nil?
-      @updated_issue.pm_project_id = @target_pm_project_id
-      @updated_issue.pm_sprint_id = @pm_sprint_id
-      @updated_issue.pm_issue_type = @pm_issue_type
-      @updated_issue.root_id = @root_id
-      @updated_issue.time_scale = @time_scale
+      @updated_issue.pm_project_id = @target_pm_project_id unless @target_pm_project_id.nil?
+      @updated_issue.pm_sprint_id = @pm_sprint_id unless @pm_sprint_id.nil?
+      @updated_issue.pm_issue_type = @pm_issue_type unless @pm_issue_type.nil?
+      @updated_issue.root_id = @root_id unless @root_id.nil?
+      @updated_issue.time_scale = @time_scale unless @time_scale.nil?
 
       @updated_issue.updated_on = Time.now
       @updated_issue.save!