diff --git a/CHANGELOG.md b/CHANGELOG.md
index 78d3756..e980f26 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ All notable changes to this project will be documented in this file.
 
 - Added post-install validations for the Wazuh manager and Filebeat. ([#3059](https://github.com/wazuh/wazuh-packages/pull/3059))
 
+### Fixed
+
+- Fixed Wazuh API validation ([#29](https://github.com/wazuh/wazuh-installation-assistant/pull/29))
+
 ## [4.9.0]
 
 - https://github.com/wazuh/wazuh-packages/releases/tag/v4.9.0
diff --git a/install_functions/manager.sh b/install_functions/manager.sh
index a33e564..862f76b 100644
--- a/install_functions/manager.sh
+++ b/install_functions/manager.sh
@@ -47,7 +47,7 @@ function manager_checkService() {
     eval "TOKEN=$(curl -k -s -X POST -u "wazuh-wui:wazuh-wui" https://127.0.0.1:55000/security/user/authenticate/run_as?raw=true -d '{"user_name":"wzread"}' -H "content-type:application/json")"
     wm_error=$(curl -k -s -X GET "https://127.0.0.1:55000/agents/outdated?pretty=true" -H "Authorization: Bearer ${TOKEN}")
 
-    if  [[ ${wm_error,,} = '"error": 0' ]]; then
+    if  [[ ${wm_error,,} =~ '"error": 0' ]]; then
         common_logger "Wazuh API connection successful"
     else
         common_logger -e "Wazuh API connection Error. $wm_error"