diff --git a/spec/jobs/get_usps_proofing_results_job_spec.rb b/spec/jobs/get_usps_proofing_results_job_spec.rb
index b184c700ac7..d34fbc6496a 100644
--- a/spec/jobs/get_usps_proofing_results_job_spec.rb
+++ b/spec/jobs/get_usps_proofing_results_job_spec.rb
@@ -572,6 +572,7 @@
             {
               status: 400,
               body: { 'responseMessage' => 'This USPS location has closed 😭' }.to_json,
+              headers: { 'content-type': 'application/json' },
             },
           )
         end