diff --git a/api-payroll/src/application/EmployeeApplication.php b/api-payroll/src/application/EmployeeApplication.php
index 988be4f..1b5483a 100644
--- a/api-payroll/src/application/EmployeeApplication.php
+++ b/api-payroll/src/application/EmployeeApplication.php
@@ -145,7 +145,11 @@ class EmployeeApplication{
         $this->asserts->betweenLength($phone, 10, 10, "The phone number must be 10 digits without special characters.");
 
         $idEmployeeType = $requestData{'idEmployeeType'};
+        $this->asserts->higherThanZero($idEmployeeType, 'idEmployeeType must be higher than zero.');
+
         $contractType = $requestData{'contractType'};
+        $this->asserts->isNotEmpty($contractType, "The contract type can't be empty.");
+        $this->asserts->existInArray($contractType, $this->settings['contractTypes'], 'The contract type is not a valid one.');
 
         // Encrypting the sensitive data
         $securedFirstName = $this->cryptographyService->encryptString($firstName);
@@ -421,6 +425,7 @@ class EmployeeApplication{
 
         $contractType = $requestData{'contractType'};
         $this->asserts->isNotEmpty($contractType, "The contract type can't be empty.");
+        $this->asserts->existInArray($contractType, $this->settings['contractTypes'], 'The contract type is not a valid one.');
 
         // Encrypting the sensitive data
         $securedFirstName = $this->cryptographyService->encryptString($firstName);
diff --git a/api-payroll/src/service/Asserts.php b/api-payroll/src/service/Asserts.php
index 3976a26..d627334 100644
--- a/api-payroll/src/service/Asserts.php
+++ b/api-payroll/src/service/Asserts.php
@@ -69,5 +69,17 @@ class Asserts{
             throw new Exception($errorMessage);
         }
     }
+
+    /**
+     * @param $string string
+     * @param $array array
+     * @param $errorMessage string
+     * @throws Exception
+     */
+    function existInArray($string, $array, $errorMessage){
+        if(!in_array($string, $array)){
+            throw new Exception($errorMessage);
+        }
+    }
 }
 ?>