diff --git a/Persistence/EntityTypeConfigurations/Schedule/GroupConfiguration.cs b/Persistence/EntityTypeConfigurations/Schedule/GroupConfiguration.cs
index 0035390..5938bb3 100644
--- a/Persistence/EntityTypeConfigurations/Schedule/GroupConfiguration.cs
+++ b/Persistence/EntityTypeConfigurations/Schedule/GroupConfiguration.cs
@@ -13,13 +13,13 @@ public class GroupConfiguration : IEntityTypeConfiguration<Group>
         builder.HasIndex(g => g.Id).IsUnique();
         builder.Property(g => g.Id).HasColumnType("INTEGER").IsRequired().ValueGeneratedOnAdd();
 
-        builder.Property(g => g.FacultyId).HasColumnType("INTEGER").IsRequired();
+        builder.Property(g => g.FacultyId).HasColumnType("INTEGER");
         builder.Property(g => g.Name).HasColumnType("TEXT").IsRequired().HasMaxLength(64);
 
         builder
             .HasOne(g => g.Faculty)
             .WithMany(u => u.Groups)
             .HasForeignKey(d => d.FacultyId)
-            .OnDelete(DeleteBehavior.Restrict);
+            .OnDelete(DeleteBehavior.SetNull);
     }
 }
\ No newline at end of file