diff --git a/workflow/engine/content/translations/english/processmaker.en.po b/workflow/engine/content/translations/english/processmaker.en.po
index 6f16a77e4..09b966a0e 100644
--- a/workflow/engine/content/translations/english/processmaker.en.po
+++ b/workflow/engine/content/translations/english/processmaker.en.po
@@ -1747,6 +1747,12 @@ msgstr "Databases Source List"
 msgid "Changes saved"
 msgstr "Changes saved"
 
+# TRANSLATION
+# LABEL/ID_SELECT_USER_OR_GROUP
+#: LABEL/ID_SELECT_USER_OR_GROUP
+msgid "Please select the name of a user or a group in the Group or User field"
+msgstr "Please select the name of a user or a group in the Group or User field"
+
 # TRANSLATION
 # LABEL/ID_EMAILS
 #: LABEL/ID_EMAILS
@@ -27869,12 +27875,6 @@ msgstr "NOT IMPORTED"
 msgid "CANNOT IMPORT"
 msgstr "CANNOT IMPORT"
 
-# TRANSLATION
-# LABEL/ID_SELECT_USER_OR_GROUP
-#: LABEL/ID_SELECT_USER_OR_GROUP
-msgid "Please select the name of a user or a group in the Group or User field"
-msgstr "Please select the name of a user or a group in the Group or User field"
-
 # additionalTables/additionalTablesData.xml?ADD_TAB_NAME
 # additionalTables/additionalTablesData.xml
 #: text - ADD_TAB_NAME
diff --git a/workflow/engine/src/ProcessMaker/BusinessModel/ProcessPermissions.php b/workflow/engine/src/ProcessMaker/BusinessModel/ProcessPermissions.php
index c16555636..ca5a754c1 100644
--- a/workflow/engine/src/ProcessMaker/BusinessModel/ProcessPermissions.php
+++ b/workflow/engine/src/ProcessMaker/BusinessModel/ProcessPermissions.php
@@ -224,6 +224,9 @@ class ProcessPermissions
             if ($opUid != '') {
                 $opUid  = $this->validateOpUid($opUid);
             }
+            if (empty($data['USR_UID']) || $data['USR_UID'] === "null") {
+                throw (new \Exception(\G::LoadTranslation("ID_SELECT_USER_OR_GROUP")));
+            }
             if ($data['OP_USER_RELATION'] == "1") {
                 $this->validateUsrUid($data['USR_UID']);
             } else {
@@ -381,7 +384,7 @@ class ProcessPermissions
     {
         $usr_uid = trim($usr_uid);
         if ($usr_uid == '') {
-            throw (new \Exception(\G::LoadTranslation("ID_SELECT_USER_OR_GROUP")));
+            throw (new \Exception(\G::LoadTranslation("ID_USER_NOT_EXIST", array('usr_uid',''))));
         }
         $oUsers = new \Users();
         if (!($oUsers->userExists($usr_uid))) {
@@ -403,7 +406,7 @@ class ProcessPermissions
     {
         $grp_uid = trim($grp_uid);
         if ($grp_uid == '') {
-            throw (new \Exception(\G::LoadTranslation("ID_SELECT_USER_OR_GROUP")));
+            throw (new \Exception(\G::LoadTranslation("ID_GROUP_NOT_EXIST", array('grp_uid',''))));
         }
         $oGroup = new \Groupwf();
         if (!($oGroup->GroupwfExists($grp_uid))) {
diff --git a/workflow/engine/src/ProcessMaker/Services/Api/Project/ProcessPermissions.php b/workflow/engine/src/ProcessMaker/Services/Api/Project/ProcessPermissions.php
index 974f18116..7b023a8da 100644
--- a/workflow/engine/src/ProcessMaker/Services/Api/Project/ProcessPermissions.php
+++ b/workflow/engine/src/ProcessMaker/Services/Api/Project/ProcessPermissions.php
@@ -58,44 +58,22 @@ class ProcessPermissions extends Api
     }
 
     /**
+     * Creates a new Process Permission for a project.
+     * 
+     * @url POST /:prj_uid/process-permission/
+     * @status 201
+     * 
      * @param string $prj_uid {@min 1} {@max 32}
      * @param array $request_data
      *
-     * @param string $usr_uid {@from body} {@min 1} {@max 32}
-     * @param string $op_user_relation {@from body} {@choice 1,2}
-     * @param string $op_case_status {@from body} {@choice ALL,DRAFT,TO_DO,PAUSED,COMPLETED}
-     * @param string $op_participate {@from body} {@choice 0,1}
-     * @param string $op_obj_type {@from body} {@choice ANY,DYNAFORM,ATTACHMENT,INPUT,OUTPUT,CASES_NOTES,MSGS_HISTORY,SUMMARY_FORM}
-     * @param string $op_action {@from body} {@choice VIEW,BLOCK,DELETE,RESEND}
-     * @param string $tas_uid {@from body}
-     * @param string $op_task_source {@from body}
-     * @param string $dynaforms {@from body}
-     * @param string $inputs {@from body}
-     * @param string $outputs {@from body}
-     *
-     * @author Brayan Pereyra (Cochalo) <brayan@colosa.com>
-     * @copyright Colosa - Bolivia
-     *
      * @return array
-     *
-     * @url POST /:prj_uid/process-permission/
-     * @status 201
+     * @throws RestException
+     * 
+     * @access protected
+     * @class AccessControl {@permission PM_FACTORY}
      */
-    public function doPostProcessPermission(
-        $prj_uid,
-        $request_data,
-        $usr_uid,
-        $op_user_relation,
-        $op_case_status,
-        $op_participate,
-        $op_obj_type,
-        $op_action,
-        $tas_uid = '',
-        $op_task_source = '',
-        $dynaforms = '',
-        $inputs = '',
-        $outputs = ''
-    ) {
+    public function doPostProcessPermission($prj_uid, $request_data)
+    {
         try {
             $hiddenFields = array('task_target', 'group_user', 'task_source',
                 'object_type', 'object', 'participated', 'action'