diff --git a/src/Tgstation.Server.Host/Utils/SignalR/ConnectionMappingHub.cs b/src/Tgstation.Server.Host/Utils/SignalR/ConnectionMappingHub.cs
index 8684901820..80e89089fa 100644
--- a/src/Tgstation.Server.Host/Utils/SignalR/ConnectionMappingHub.cs
+++ b/src/Tgstation.Server.Host/Utils/SignalR/ConnectionMappingHub.cs
@@ -6,8 +6,6 @@ using Microsoft.AspNetCore.SignalR;
 
 using Tgstation.Server.Host.Security;
 
-#nullable disable
-
 namespace Tgstation.Server.Host.Utils.SignalR
 {
 	/// <summary>
@@ -52,7 +50,7 @@ namespace Tgstation.Server.Host.Utils.SignalR
 
 		/// <inheritdoc />
 		[AllowAnonymous]
-		public override Task OnDisconnectedAsync(Exception exception)
+		public override Task OnDisconnectedAsync(Exception? exception)
 		{
 			connectionMapper.UserDisconnected(Context.ConnectionId);
 			return base.OnDisconnectedAsync(exception);