Minor identity bugfix (#10050)

Content.Server/IdentityManagement/IdentitySystem.cs

@@ -141,7 +141,7 @@ public class IdentitySystem : SharedIdentitySystem
         // Get their name and job from their ID for their presumed name.
         if (_idCard.TryFindIdCard(target, out var id))
         {
-            presumedName = id.FullName;
+            presumedName = string.IsNullOrWhiteSpace(id.FullName) ? null : id.FullName;
             presumedJob = id.JobTitle?.ToLowerInvariant();
         }