diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
index e26fd96..043a606 100644
--- a/.github/.OwlBot.lock.yaml
+++ b/.github/.OwlBot.lock.yaml
@@ -1,3 +1,3 @@
 docker:
   image: gcr.io/repo-automation-bots/owlbot-nodejs:latest
-  digest: sha256:b94b09fb24bf804090b8cc60ee726ca161d5e5915151e417f8ef5d8bcfe73cbc
+  digest: sha256:f4734af778c3d0eb58a6db0078907a87f2e53f3c7a6422363fc37ee52e02b25a
diff --git a/.github/generated-files-bot.yml b/.github/generated-files-bot.yml
index 1b3ef1c..6b04910 100644
--- a/.github/generated-files-bot.yml
+++ b/.github/generated-files-bot.yml
@@ -11,3 +11,6 @@ generatedFiles:
   message: '`README.md` is managed by [`synthtool`](https://github.com/googleapis/synthtool). However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/master/.readme-partials.yaml'
 - path: 'samples/README.md'
   message: '`samples/README.md` is managed by [`synthtool`](https://github.com/googleapis/synthtool). However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/master/.readme-partials.yaml'
+ignoreAuthors:
+- 'gcf-owl-bot[bot]'
+- 'yoshi-automation'
diff --git a/CHANGELOG.md b/CHANGELOG.md
index c508871..e32d5a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+### [3.1.2](https://www.github.com/googleapis/nodejs-service-directory/compare/v3.1.1...v3.1.2) (2021-05-25)
+
+
+### Bug Fixes
+
+* GoogleAdsError missing using generator version after 1.3.0 ([#144](https://www.github.com/googleapis/nodejs-service-directory/issues/144)) ([631084d](https://www.github.com/googleapis/nodejs-service-directory/commit/631084de940c87b6d53404d6e5299ac11f8a6740))
+
 ### [3.1.1](https://www.github.com/googleapis/nodejs-service-directory/compare/v3.1.0...v3.1.1) (2021-05-12)
 
 
diff --git a/package.json b/package.json
index 00a1503..359002f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@google-cloud/service-directory",
-  "version": "3.1.1",
+  "version": "3.1.2",
   "description": "Servicedirectory client for Node.js",
   "repository": "googleapis/nodejs-service-directory",
   "license": "Apache-2.0",
@@ -34,7 +34,7 @@
   },
   "devDependencies": {
     "@types/mocha": "^8.0.0",
-    "@types/node": "^12.12.29",
+    "@types/node": "^14.0.0",
     "@types/sinon": "^10.0.0",
     "c8": "^7.1.0",
     "gts": "^3.0.0",
@@ -45,7 +45,7 @@
     "mocha": "^8.0.0",
     "null-loader": "^4.0.0",
     "pack-n-play": "^1.0.0-2",
-    "sinon": "^10.0.0",
+    "sinon": "^11.0.0",
     "ts-loader": "^9.0.0",
     "typescript": "^3.8.3",
     "@microsoft/api-documenter": "^7.8.10",
diff --git a/samples/package.json b/samples/package.json
index 8bc7271..cc2e3a3 100644
--- a/samples/package.json
+++ b/samples/package.json
@@ -13,7 +13,7 @@
     "test": "c8 mocha --timeout 600000 test/*.js"
   },
   "dependencies": {
-    "@google-cloud/service-directory": "^3.1.1",
+    "@google-cloud/service-directory": "^3.1.2",
     "eslint": "^7.0.0",
     "json-schema": "^0.3.0",
     "uuid": "^8.0.0"
diff --git a/src/v1/lookup_service_client.ts b/src/v1/lookup_service_client.ts
index f92bd62..a68f090 100644
--- a/src/v1/lookup_service_client.ts
+++ b/src/v1/lookup_service_client.ts
@@ -131,6 +131,8 @@ export class LookupServiceClient {
     }
     if (!opts.fallback) {
       clientHeader.push(`grpc/${this._gaxGrpc.grpcVersion}`);
+    } else if (opts.fallback === 'rest') {
+      clientHeader.push(`rest/${this._gaxGrpc.grpcVersion}`);
     }
     if (opts.libName && opts.libVersion) {
       clientHeader.push(`${opts.libName}/${opts.libVersion}`);
diff --git a/src/v1/registration_service_client.ts b/src/v1/registration_service_client.ts
index 35819a4..28434e4 100644
--- a/src/v1/registration_service_client.ts
+++ b/src/v1/registration_service_client.ts
@@ -154,6 +154,8 @@ export class RegistrationServiceClient {
     }
     if (!opts.fallback) {
       clientHeader.push(`grpc/${this._gaxGrpc.grpcVersion}`);
+    } else if (opts.fallback === 'rest') {
+      clientHeader.push(`rest/${this._gaxGrpc.grpcVersion}`);
     }
     if (opts.libName && opts.libVersion) {
       clientHeader.push(`${opts.libName}/${opts.libVersion}`);
diff --git a/src/v1beta1/lookup_service_client.ts b/src/v1beta1/lookup_service_client.ts
index 000ded2..6424e4f 100644
--- a/src/v1beta1/lookup_service_client.ts
+++ b/src/v1beta1/lookup_service_client.ts
@@ -131,6 +131,8 @@ export class LookupServiceClient {
     }
     if (!opts.fallback) {
       clientHeader.push(`grpc/${this._gaxGrpc.grpcVersion}`);
+    } else if (opts.fallback === 'rest') {
+      clientHeader.push(`rest/${this._gaxGrpc.grpcVersion}`);
     }
     if (opts.libName && opts.libVersion) {
       clientHeader.push(`${opts.libName}/${opts.libVersion}`);
diff --git a/src/v1beta1/registration_service_client.ts b/src/v1beta1/registration_service_client.ts
index 168230d..50a21ea 100644
--- a/src/v1beta1/registration_service_client.ts
+++ b/src/v1beta1/registration_service_client.ts
@@ -154,6 +154,8 @@ export class RegistrationServiceClient {
     }
     if (!opts.fallback) {
       clientHeader.push(`grpc/${this._gaxGrpc.grpcVersion}`);
+    } else if (opts.fallback === 'rest') {
+      clientHeader.push(`rest/${this._gaxGrpc.grpcVersion}`);
     }
     if (opts.libName && opts.libVersion) {
       clientHeader.push(`${opts.libName}/${opts.libVersion}`);