diff --git a/lib/models/dns_statistics.dart b/lib/models/dns_statistics.dart
index f279886..ca6c247 100644
--- a/lib/models/dns_statistics.dart
+++ b/lib/models/dns_statistics.dart
@@ -5,7 +5,7 @@ DnsStatistics dnsStatisticsFromJson(String str) => DnsStatistics.fromJson(json.d
 String dnsStatisticsToJson(DnsStatistics data) => json.encode(data.toJson());
 
 class DnsStatistics {
-  final String timeUnits;
+  final String? timeUnits;
   final List<Map<String, int>> topQueriedDomains;
   final List<Map<String, int>> topClients;
   final List<Map<String, int>> topBlockedDomains;
diff --git a/lib/providers/dns_provider.dart b/lib/providers/dns_provider.dart
index 198053b..a59c3c5 100644
--- a/lib/providers/dns_provider.dart
+++ b/lib/providers/dns_provider.dart
@@ -151,20 +151,26 @@ class DnsProvider with ChangeNotifier {
     final result = await _serversProvider!.apiClient2!.setDnsConfig(
       data: value
     );
+    
+    void updateValue(dynamic parameter, dynamic value) {
+      if (value != null) {
+        parameter = value;
+      }
+    }
 
     if (result.successful == true) {
       DnsInfo data = dnsInfo!;
-      data.ratelimit = value['ratelimit'];
-      data.ednsCsEnabled = value['edns_cs_enabled'];
-      data.dnssecEnabled = value['dnssec_enabled'];
-      data.disableIpv6 = value['disable_ipv6'];
-      data.blockingMode = value['blocking_mode'];
-      data.blockingIpv4 = value['blocking_ipv4'];
-      data.blockingIpv6 = value['blocking_ipv6'];
-      data.blockedResponseTtl = value['blocked_response_ttl'];
-      data.ratelimitSubnetLenIpv4 = value['ratelimit_subnet_len_ipv4'];
-      data.ratelimitSubnetLenIpv6 = value['ratelimit_subnet_len_ipv6'];
-      data.ratelimitWhitelist = value['ratelimit_whitelist'];
+      updateValue(data.ratelimit, value['ratelimit']);
+      updateValue(data.ednsCsEnabled, value['edns_cs_enabled']);
+      updateValue(data.dnssecEnabled, value['dnssec_enabled']);
+      updateValue(data.disableIpv6, value['disable_ipv6']);
+      updateValue(data.blockingMode, value['blocking_mode']);
+      updateValue(data.blockingIpv4, value['blocking_ipv4']);
+      updateValue(data.blockingIpv6, value['blocking_ipv6']);
+      updateValue(data.blockedResponseTtl, value['blocked_response_ttl']);
+      updateValue(data.ratelimitSubnetLenIpv4, value['ratelimit_subnet_len_ipv4']);
+      updateValue(data.ratelimitSubnetLenIpv6, value['ratelimit_subnet_len_ipv6']);
+      updateValue(data.ratelimitWhitelist, value['ratelimit_whitelist']);
       setDnsInfoData(data);
       return result;
     }
diff --git a/lib/screens/filters/add_button.dart b/lib/screens/filters/add_button.dart
index 2eca7d4..1621b68 100644
--- a/lib/screens/filters/add_button.dart
+++ b/lib/screens/filters/add_button.dart
@@ -137,6 +137,8 @@ class AddFiltersButton extends StatelessWidget {
     }
 
     void confirmAddList({required String name, required String url, required String type}) async {
+      if (!context.mounted) return;
+
       ProcessModal processModal = ProcessModal();
       processModal.open(AppLocalizations.of(context)!.addingList);
 
diff --git a/lib/screens/filters/custom_rules_list.dart b/lib/screens/filters/custom_rules_list.dart
index 304972f..4cd5bde 100644
--- a/lib/screens/filters/custom_rules_list.dart
+++ b/lib/screens/filters/custom_rules_list.dart
@@ -162,7 +162,7 @@ class _CustomRulesListState extends State<CustomRulesList> {
             TextButton.icon(
               onPressed: () async {
                 final result = await filteringProvider.fetchFilters();
-                if (result == false) {
+                if (result == false && context.mounted) {
                   showSnackbar(
                     appConfigProvider: appConfigProvider,
                     label: AppLocalizations.of(context)!.errorLoadFilters, 
diff --git a/lib/screens/home/appbar.dart b/lib/screens/home/appbar.dart
index 5cd481f..d4b447c 100644
--- a/lib/screens/home/appbar.dart
+++ b/lib/screens/home/appbar.dart
@@ -34,6 +34,7 @@ class HomeAppBar extends StatelessWidget {
 
     void navigateServers() {
       Future.delayed(const Duration(milliseconds: 0), (() {
+        if (!context.mounted) return;
         Navigator.of(context).push(
           MaterialPageRoute(builder: (context) => const Servers())
         );
diff --git a/lib/screens/logs/filters/clients_modal.dart b/lib/screens/logs/filters/clients_modal.dart
index 403f098..ef0e989 100644
--- a/lib/screens/logs/filters/clients_modal.dart
+++ b/lib/screens/logs/filters/clients_modal.dart
@@ -115,7 +115,7 @@ class _ClientsModalState extends State<ClientsModal> {
 
     void searchAddedClient(_ClientLog client) {
       final notIps = client.ids?.where((e) => isIpAddress(e) == false).toList();
-      if (notIps == null) return;
+      if (notIps == null || notIps.isEmpty) return;
       logsProvider.setSearchText('"${notIps[0]}"');
       Navigator.of(context).pop();
     }
diff --git a/lib/screens/logs/log_tile.dart b/lib/screens/logs/log_tile.dart
index bed2e40..342817f 100644
--- a/lib/screens/logs/log_tile.dart
+++ b/lib/screens/logs/log_tile.dart
@@ -96,6 +96,8 @@ class LogTile extends StatelessWidget {
     }
 
     void blockUnblock({required String domain, required String newStatus}) async {
+      if (!context.mounted) return;
+      
       final ProcessModal processModal = ProcessModal();
       processModal.open(AppLocalizations.of(context)!.savingUserFilters);
 
@@ -124,6 +126,8 @@ class LogTile extends StatelessWidget {
     }
 
     void confirmAddClient(Client client) async {
+      if (!context.mounted) return;
+
       ProcessModal processModal = ProcessModal();
       processModal.open(AppLocalizations.of(context)!.addingClient);
       
diff --git a/lib/screens/settings/statistics_settings/statistics_settings.dart b/lib/screens/settings/statistics_settings/statistics_settings.dart
index 67a2989..7f58d67 100644
--- a/lib/screens/settings/statistics_settings/statistics_settings.dart
+++ b/lib/screens/settings/statistics_settings/statistics_settings.dart
@@ -138,7 +138,7 @@ class _StatisticsSettingsState extends State<StatisticsSettings> {
           "enabled": _generalSwitch,
           "interval": _retentionTime == "custom" 
             ? Duration(hours: int.parse(_customTimeController.text)).inMilliseconds 
-            : int.parse(_retentionTime!),
+            : int.parse(_retentionTime ?? _retentionItems[0]),
           "ignored": _ignoredDomainsControllers.map((e) => e.controller.text).toList()
         }
       );