Unit test success individually, but after running all tests some fails - sql-server

Question

I'm using Microsoft.EntityFrameworkCore.InMemory/3.1.16.
my tests pass when I run them individually but when I run all tests some of them fail.
Sdk :.net core 3.1
here is my optionbuilder configuration:
public static DbContextOptionsBuilder<T> GetDbContextOptionsBuilder<T>( string? connectionString =null , Guid? databaseId = null)
where T : DbContext
{
var optionBuilder = new DbContextOptionsBuilder<T>();
if (databaseId is null)
databaseId = Guid.NewGuid();
optionBuilder.UseInMemoryDatabase( $"dbApi-{databaseId:N}",
x => {
x.UseHierarchyId();
} )
.EnableSensitiveDataLogging()
.EnableDetailedErrors();
return optionBuilder;
}
public static DbContextOptionsBuilder<T> GetInDbContextOptionsBuilder<T>( IConfiguration configuration )
where T : DbContext
{
configuration ??= ConfigHelper.GetConfig();
return GetDbContextOptionsBuilder<T>( configuration.GetConnectionString( "DefaultConnection" ) );
}
and how my unit tests call dbContext like this:
await using var db = new WriteContext(DbContextInitialization.GetDbContextOptionsBuilder<WriteContext>().Options);
in tests I seed some data like this:
db.SeedTemplate(); //test 1
db.SeedCategory(); //test 2
when I run the tests it throws following error:
The instance of entity type 'entity' cannot be tracked because another instance with the key value '{Id: 1}' is already being tracked. When attaching existing entities, ensure that only one entity instance with a given key value is attached.
Edit 1:
I add two sample tests:
//This test will pass
[Fact]
public async Task Can_Add_Template_With_Attribute()
{
await using var db = new WriteContext(DbContextInitialization.GetDbContextOptionsBuilder<WriteContext>().Options);
//priceAttribute and displayAttribute removed for brevity
template.LinkAttributes( new List<Attribute>{ priceAttribute,displayAttribute} );
await db.Templates.AddAsync( template);
await db.SaveChangesAsync();
var actualTemplate = await db.Templates.FirstAsync();
actualTemplate.ShouldNotBeNull();
actualTemplate.Attributes.First().ShouldEqual( priceAttribute ););
}
//This test will throw error
[Fact]
public async Task Can_Delete_Template()
{
await using var db = new WriteContext(DbContextInitialization.GetDbContextOptionsBuilder<WriteContext>().Options, MediatorHelper.Initialize());
//priceAttribute and displayAttribute removed for brevity
template.LinkAttributes( new List<Attribute>{ priceAttribute,displayAttribute} );
await db.Templates.AddAsync( template);
await db.SaveChangesAsync();
template.Delete();
var command = new DeleteTemplateCommand( template.Id );
var handler = new DeleteTemplateCommand.DeleteTemplateCommandHandler( db );
var result=await handler.Handle( command,CancellationToken.None );
result.Should().BeSuccess();
var actualTemplate = await db.Templates.FirstAsync();
actualTemplate.IsDeleted.ShouldBeTrue();
}