diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2f95087..81cb6b4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Change Log
 
+## [v4.26.1](https://github.com/plivo/plivo-node/tree/v4.26.1) (2022-01-21)
+**Bug Fix**
+- Making AppId non mandatory for Buy number and update number APIs(https://github.com/plivo/plivo-node/pull/234)
+
 ## [v4.26.0](https://github.com/plivo/plivo-node/tree/v4.26.0) (2021-12-14)
 **Features - Voice**
 - Routing SDK traffic through Akamai endpoints for all the [Voice APIs](https://www.plivo.com/docs/voice/api/overview/)
diff --git a/package.json b/package.json
index 132fc25..7853d66 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "plivo",
-  "version": "4.26.0",
+  "version": "4.26.1",
   "description": "A Node.js SDK to make voice calls and send SMS using Plivo and to generate Plivo XML",
   "homepage": "https://github.com/plivo/plivo-node",
   "files": [
diff --git a/types/resources/numbers.d.ts b/types/resources/numbers.d.ts
index 19cceca..30cf8b1 100644
--- a/types/resources/numbers.d.ts
+++ b/types/resources/numbers.d.ts
@@ -48,7 +48,7 @@ export class PhoneNumber extends PlivoResource {
 	 * @promise {@link PlivoGenericResponse} return PlivoGenericResponse Object if success
 	 * @fail {Error} return Error
 	 */
-	buy(appId: string): Promise < any > ;
+	buy(appId?: string): Promise < any > ;
 	[clientKey]: symbol;
 }
 /**
@@ -67,7 +67,7 @@ export class PhoneNumberInterface extends PlivoResourceInterface {
 	 * @promise {@link PlivoGenericResponse} return PlivoGenericResponse Object if success
 	 * @fail {Error} return Error
 	 */
-	buy(number: string, appId: string): Promise < any > ;
+	buy(number: string, appId?: string): Promise < any > ;
 	[clientKey]: symbol;
 }
 /**
@@ -104,7 +104,7 @@ export class NumberInterface extends PlivoResourceInterface {
 	 * @promise {@link PlivoGenericResponse} return PlivoGenericResponse Object if success
 	 * @fail {Error} return Error
 	 */
-	buy(number: string, appId: string): Promise < BuyNumberResponse > ;
+	buy(number: string, appId?: string): Promise < BuyNumberResponse > ;
 	/**
 	 * Add own number from carrier
 	 * @method
@@ -124,7 +124,7 @@ export class NumberInterface extends PlivoResourceInterface {
 	 * @promise {@link PhoneNumberInterface} return PhoneNumbers Object if success
 	 * @fail {Error} return Error
 	 */
-	search(countryISO: string, optionalParams: object): Promise < SearchNumberResponse > ;
+	search(countryISO: string, optionalParams: object): Promise < SearchNumberResponse[] > ;
 	/**
 	 * Update Number
 	 * @method