diff --git a/ui/public/i18n/en/translation.json b/ui/public/i18n/en/translation.json
index c1706ad..a6fe410 100644
--- a/ui/public/i18n/en/translation.json
+++ b/ui/public/i18n/en/translation.json
@@ -107,6 +107,8 @@
     "loki_retention_min": "Logs retention must be greater than 1 day",
     "invalid_network": "Invalid network, it mus be a class C network like 192.168.200.0",
     "invalid_netmask": "Invalid netmask, it must be a valid netmask like 255.255.255.0",
-    "invalid_allowed_ips": "Invalid allowed IPs, each entry must be a and IP or CIDR network."
+    "invalid_allowed_ips": "Invalid allowed IPs, each entry must be a and IP or CIDR network.",
+    "tun_mtu_min": "TUN MTU must be at least 576",
+    "mssfix_min": "MSS Fix must be at least 0"
   }
 }
diff --git a/ui/public/i18n/es/translation.json b/ui/public/i18n/es/translation.json
index f688828..dec8a58 100644
--- a/ui/public/i18n/es/translation.json
+++ b/ui/public/i18n/es/translation.json
@@ -12,7 +12,9 @@
         "404": "Recurso no encontrado",
         "invalid_user": "Nombre de usuario no válido: debe contener sólo letras y números",
         "network_error": "Error de red",
-        "validation_error": "Error de validación"
+        "validation_error": "Error de validación",
+        "tun_mtu_min": "TUN MTU debe ser al menos 576",
+        "mssfix_min": "MSS Fix debe ser al menos 0"
     },
     "settings": {
         "user": "Usuario administrador",
diff --git a/ui/public/i18n/it/translation.json b/ui/public/i18n/it/translation.json
index 5b11311..8c9bc9e 100644
--- a/ui/public/i18n/it/translation.json
+++ b/ui/public/i18n/it/translation.json
@@ -12,7 +12,9 @@
         "403": "Operazione non autorizzata",
         "invalid_cn": "Nome controller non valido: deve contenere solo lettere e numeri",
         "invalid_user": "Nome utente non valido: deve contenere solo lettere e numeri",
-        "invalid_host": "Nome host non valido: deve essere un FQDN valido"
+        "invalid_host": "Nome host non valido: deve essere un FQDN valido",
+        "tun_mtu_min": "TUN MTU deve essere almeno 576",
+        "mssfix_min": "MSS Fix deve essere almeno 0"
     },
     "settings": {
         "title": "Impostazioni",
diff --git a/ui/src/views/Settings.vue b/ui/src/views/Settings.vue
index 7216e18..e83c489 100644
--- a/ui/src/views/Settings.vue
+++ b/ui/src/views/Settings.vue
@@ -589,14 +589,16 @@ export default {
       }
 
       // validate tun_mtu: minimum 576
-      if (parseInt(this.tun_mtu) < 576) {
+      const tunMtuValue = parseInt(this.tun_mtu, 10);
+      if (isNaN(tunMtuValue) || tunMtuValue < 576) {
         this.error.tun_mtu = this.$t("error.tun_mtu_min");
         this.focusElement("tun_mtu");
         isValidationOk = false;
       }
 
       // validate mssfix: minimum 0
-      if (parseInt(this.mssfix) < 0) {
+      const mssfixValue = parseInt(this.mssfix, 10);
+      if (isNaN(mssfixValue) || mssfixValue < 0) {
         this.error.mssfix = this.$t("error.mssfix_min");
         this.focusElement("mssfix");
         isValidationOk = false;
@@ -699,11 +701,11 @@ export default {
         ovpn_netmask: this.netmask,
         ovpn_cn: this.cn,
         api_user: this.user,
-        loki_retention: parseInt(this.loki_retention),
-        prometheus_retention: parseInt(this.prometheus_retention),
+        loki_retention: parseInt(this.loki_retention, 180),
+        prometheus_retention: parseInt(this.prometheus_retention, 15),
         maxmind_license: this.maxmind_license,
-        tun_mtu: parseInt(this.tun_mtu),
-        mssfix: parseInt(this.mssfix),
+        tun_mtu: parseInt(this.tun_mtu, 1500),
+        mssfix: parseInt(this.mssfix, 1455),
         allowed_ips: this.allowed_ips
           .split("\n")
           .map((ip) => ip.trim())