修复

app/views/api/v1/issues/_detail.json.jbuilder

@@ -59,7 +59,7 @@ json.pm_project_id issue.pm_project_id
 json.time_scale issue.time_scale
 json.child_count issue.child_count
 json.project do 
-  if issue.project.present? && issue.owner.present?
+  if issue.project.present? && issue.project&.owner.present?
     json.partial! "api/v1/projects/detail", locals: {project: issue.project}
   else 
     json.nil!