diff --git a/lib/entitlements/backend/github_org/service.rb b/lib/entitlements/backend/github_org/service.rb
index 65ce75f..17062e0 100644
--- a/lib/entitlements/backend/github_org/service.rb
+++ b/lib/entitlements/backend/github_org/service.rb
@@ -54,6 +54,9 @@ def add_user_to_organization(user, role)
 
             Entitlements.logger.warn "User #{user} not found in GitHub instance #{identifier}, ignoring."
             return false
+          rescue Octokit::UnprocessableEntity => e
+            Entitlements.logger.warn "Unprocessable entity when adding #{user} to organization #{org} with role #{role}: #{e.message}. This likely means the user blocked the invite, so we're ignoring them, but someone should check it."
+            return false
           end
 
           # Happy path
diff --git a/lib/version.rb b/lib/version.rb
index 412c637..06191dc 100644
--- a/lib/version.rb
+++ b/lib/version.rb
@@ -2,6 +2,6 @@
 
 module Entitlements
   module Version
-    VERSION = "1.2.1"
+    VERSION = "1.2.2"
   end
 end
diff --git a/spec/unit/entitlements/backend/github_org/service_spec.rb b/spec/unit/entitlements/backend/github_org/service_spec.rb
index 6aebce7..05c8a99 100644
--- a/spec/unit/entitlements/backend/github_org/service_spec.rb
+++ b/spec/unit/entitlements/backend/github_org/service_spec.rb
@@ -201,6 +201,28 @@
           expect(result).to eq(false)
         end
       end
+
+      context "when the API returns an unprocessable entity error" do
+        it "warns and returns false" do
+          expect(logger).to receive(:debug).with("github.fake add_user_to_organization(user=bob, org=kittensinc, role=admin)")
+          expect(logger).to receive(:debug).with("Setting up GitHub API connection to https://github.fake/api/v3/")
+          expect(logger).to receive(:warn).with(/Unprocessable entity when adding bob to organization kittensinc with role admin.*likely means the user blocked the invite/)
+
+          stub_request(:put, "https://github.fake/api/v3/orgs/kittensinc/memberships/bob").to_return(
+            status: 422,
+            headers: {
+              "Content-type" => "application/json"
+            },
+            body: JSON.generate({
+              "message"           => "Unprocessable Entity",
+              "documentation_url" => "https://docs.github.com/rest"
+            })
+          )
+
+          result = subject.send(:add_user_to_organization, "bob", "admin")
+          expect(result).to eq(false)
+        end
+      end
     end
   end