diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0cc68b0..1887d77 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,12 @@
 # Changelog
+### [1.5.1](https://github.com/ratepay/php-library/compare/1.5.0...1.5.1) (2021-07-13)
+
+
+### Bug Fixes
+
+* missing model mapping for multiple tracking ids ([a0d8d99](https://github.com/ratepay/php-library/commit/a0d8d99873f5ae9c8c3c20e0bac2fb50cd5d0d0b))
+* multiple tracking ids: fix missing model mapping ([eebea1a](https://github.com/ratepay/php-library/commit/eebea1aca578d1e8cc758edd20c97f0773e16e90))
+
 ## [1.5.0](https://github.com/ratepay/php-library/compare/1.4.0...1.5.0) (2021-06-10)
 
 
diff --git a/README.md b/README.md
index a0325ad..b01538f 100755
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ RatePAY Integration Toolkit for PHP
 | Repository | Common RatePAY PHP Library
 |------------|----------
 | Author     | Eduardo Iriarte-Mendez
-| Version    | `1.5.0` [Changelog](./CHANGELOG.md)
+| Version    | `1.5.1` [Changelog](./CHANGELOG.md)
 | Link       | http://www.ratepay.com
 | Mail       | integration@ratepay.com
 
diff --git a/composer.json b/composer.json
index c17da30..4aee7e1 100755
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
   "name": "ratepay/php-library",
   "description": "Ratepay Payment-API PHP Library",
-  "version": "1.5.0",
+  "version": "1.5.1",
   "license": "MIT",
   "type": "library",
   "homepage": "https://ratepay.gitbook.io/docs/",
diff --git a/src/Model/Request/SubModel/Constants.php b/src/Model/Request/SubModel/Constants.php
index 5f96e03..8d3a381 100755
--- a/src/Model/Request/SubModel/Constants.php
+++ b/src/Model/Request/SubModel/Constants.php
@@ -23,7 +23,7 @@ class Constants
     /**
      * Library version.
      */
-    const LIBRARY_VERSION = '1.5.0';
+    const LIBRARY_VERSION = '1.5.1';
 
     /**
      * Supported RatePAY API version.