Postgres ERROR: tuple concurrently updated

I have a large table test in which in user_id 2 have 500000 records. So I want to delete this record in chunks of 100 records but it is given error. Here is my query: delete from test where test_id in (select test_id from test where User_id = 2 limit 100 ) > ERROR: tuple concurrently updated What is the issue. How can i solved it.