diff --git a/Netch/Servers/Shadowsocks/SSUtil.cs b/Netch/Servers/Shadowsocks/SSUtil.cs
index 5526e73c..aa3a93be 100644
--- a/Netch/Servers/Shadowsocks/SSUtil.cs
+++ b/Netch/Servers/Shadowsocks/SSUtil.cs
@@ -76,7 +76,7 @@ namespace Netch.Servers.Shadowsocks
 
         public IEnumerable<Server> ParseSsdUri(string s)
         {
-            var json = JsonSerializer.Deserialize<Main>(ShareLink.URLSafeBase64Decode(s.Substring(6)));
+            var json = JsonSerializer.Deserialize<Main>(ShareLink.URLSafeBase64Decode(s.Substring(6)))!;
 
             return json.servers.Select(server => new Shadowsocks
                 {
diff --git a/Netch/Servers/VMess/VMessUtil.cs b/Netch/Servers/VMess/VMessUtil.cs
index a57d062c..4c220563 100644
--- a/Netch/Servers/VMess/VMessUtil.cs
+++ b/Netch/Servers/VMess/VMessUtil.cs
@@ -97,7 +97,7 @@ namespace Netch.Servers.VMess
 
             if (data.TransferProtocol == "quic")
             {
-                if (VMessGlobal.QUIC.Contains(vmess.host))
+                if (VMessGlobal.QUIC.Contains(vmess.host!))
                 {
                     data.QUICSecure = vmess.host;
                     data.QUICSecret = vmess.path;
diff --git a/Netch/Utils/i18N.cs b/Netch/Utils/i18N.cs
index 1ad8e74a..9062e088 100644
--- a/Netch/Utils/i18N.cs
+++ b/Netch/Utils/i18N.cs
@@ -57,7 +57,7 @@ namespace Netch.Utils
                     break;
             }
 
-            var dictionary = JsonSerializer.Deserialize<Dictionary<string, string>>(text);
+            var dictionary = JsonSerializer.Deserialize<Dictionary<string, string>>(text)!;
 
             if (!dictionary.Any())
             {