diff --git a/app/controllers/api/v1/projects/branches_controller.rb b/app/controllers/api/v1/projects/branches_controller.rb
index a4794b61a..40f44fea5 100644
--- a/app/controllers/api/v1/projects/branches_controller.rb
+++ b/app/controllers/api/v1/projects/branches_controller.rb
@@ -50,7 +50,7 @@ class Api::V1::Projects::BranchesController < Api::V1::BaseController
   end
 
   def close_pull_requests_by(project, branch_name)
-    open_pull_requests = project.pull_requests.opening.where(head: branch_name).or(a.pull_requests.opening.where(base: branch_name))
+    open_pull_requests = project.pull_requests.opening.where(head: branch_name).or(project.pull_requests.opening.where(base: branch_name))
     if open_pull_requests.present?
       open_pull_requests.each do |pull_request|
         closed = PullRequests::CloseService.call(project.owner, project.repository, pull_request, current_user)