Bulk insert issue with GUID primary key

[SivaTR]

I got below error when try to insert multiple values.

I am using postgresql , For primary key am using gen_random_uuid().

Npgsql.PostgresException
HResult=0x80004005
Message=23505: duplicate key value violates unique constraint "test_pkey"

DETAIL: Detail redacted as it may contain sensitive data. Specify 'Include Error Detail' in the connection string to include this information.
Source=Npgsql
StackTrace:
at Npgsql.Internal.NpgsqlConnector.d__233.MoveNext()
at System.Runtime.CompilerServices.PoolingAsyncValueTaskMethodBuilder1.StateMachineBox1.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
at Npgsql.NpgsqlDataReader.d__52.MoveNext()
at Npgsql.NpgsqlDataReader.d__52.MoveNext()
at Npgsql.NpgsqlDataReader.NextResult()
at Npgsql.NpgsqlCommand.d__119.MoveNext()
at Npgsql.NpgsqlCommand.d__119.MoveNext()
at System.Threading.Tasks.ValueTask1.get_Result() at Npgsql.NpgsqlCommand.ExecuteReader(CommandBehavior behavior) at Npgsql.Bulk.NpgsqlBulkUploader.InsertPortion[T](IEnumerable1 list, List1 insertParts, NpgsqlConnection conn, NpgsqlBulkCodeBuilder1 codeBuilder, String tempTableName, EntityInfo entityInfo, InsertConflictAction onConflict)
at Npgsql.Bulk.NpgsqlBulkUploader.Insert[T](IEnumerable1 entities, InsertConflictAction onConflict) at Npgsql.Bulk.NpgsqlBulkUploader.Insert[T](IEnumerable1 entities)
at TestBulkInsert.SqlBulkHandler.Insert[T](IEnumerable`1 entities) in C:\Users\TestBulkInsert\TestBulkInsert\SqlBulkHandler.cs:line 19
at Program.

$(String[] args) in C:\Users\TestBulkInsert\TestBulkInsert\Program.cs:line 125