diff --git a/jams-react-client/src/views/Groups/Groups.js b/jams-react-client/src/views/Groups/Groups.js
index 9399fa7c9a39ca7456c10415876237723fe3705f..d8286e2d87850971baad91dbe7ae7e12954639e8 100644
--- a/jams-react-client/src/views/Groups/Groups.js
+++ b/jams-react-client/src/views/Groups/Groups.js
@@ -204,7 +204,7 @@ export default function Groups() {
         let blueprintsOptions = []
         let index = 0
         if(blueprints.length === 0)
-            blueprintsOptions.push({ value: index, label: "No blueprint found"})
+            blueprintsOptions.push({value: index, label: "No blueprint found"})
         else {
             blueprints.map((blueprint) => {
                 blueprintsOptions.push({value: index, label: blueprint.name})
@@ -283,6 +283,7 @@ export default function Groups() {
                                         onChange={handleBlueprintsChange}
                                         variant="outlined"
                                         children={blueprintsOptionsItems}
+                                        disabled={blueprints.length === 0}
                                     />
                                 </Grid>
                             </Grid>
diff --git a/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/GroupServlet.java b/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/GroupServlet.java
index ad6b445647ceb47a2f3c6dc5698bf49ec17b5698..efb4509a4f28d6bd1cc07144da85dbed03c69af5 100644
--- a/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/GroupServlet.java
+++ b/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/GroupServlet.java
@@ -7,6 +7,7 @@ import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import lombok.extern.slf4j.Slf4j;
+import net.jami.jams.common.annotations.JsonContent;
 import net.jami.jams.common.annotations.ScopedServletMethod;
 import net.jami.jams.common.dao.StatementElement;
 import net.jami.jams.common.dao.StatementList;
diff --git a/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/PolicyServlet.java b/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/PolicyServlet.java
index c854f9fea021150f1a559ff2699c6a229d2298e0..a97ecb993586c6a9dc83d9ff3aad00171845322f 100644
--- a/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/PolicyServlet.java
+++ b/jams-server/src/main/java/net/jami/jams/server/servlets/api/admin/group/PolicyServlet.java
@@ -6,6 +6,7 @@ import jakarta.servlet.annotation.WebServlet;
 import jakarta.servlet.http.HttpServlet;
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
+import net.jami.jams.common.annotations.JsonContent;
 import net.jami.jams.common.annotations.ScopedServletMethod;
 import net.jami.jams.common.dao.StatementElement;
 import net.jami.jams.common.dao.StatementList;
@@ -24,6 +25,7 @@ public class PolicyServlet extends HttpServlet {
 
     @Override
     @ScopedServletMethod(securityGroups = {AccessLevel.ADMIN})
+    @JsonContent
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {