Hello!

I am using Oracle DB with "Flashback Data Archive" enabled.

I try to get one row as it was some time ago. For this I do "as of query"

But I got 2 rows instead of 1, although ID is Primary Key:

SQL> SELECT ID, STATE$DOC
  2  FROM   WB.CLAIMS AS OF TIMESTAMP TO_TIMESTAMP('2020-09-04 13:34:12', 'YYYY-MM-DD HH24:MI:SS')
  3  WHERE ID = 521228;

        ID STATE$DOC
---------- -------------------------------
    521228 Draft
    521228 Confirmed

query with AS OF SCN:

SQL> SELECT ID, STATE$DOC
  2  FROM   WB.CLAIMS AS OF  SCN timestamp_to_scn ( TO_TIMESTAMP('2020-09-03 13:34:12', 'YYYY-MM-DD HH24:MI:SS'))
  3  WHERE ID = 521228;

        ID STATE$DOC
---------- -------------------------------------------------------------------------------------------------------------------------
    521228 Draft
    521228 Confirmed

Is something wrong with database?
Or this is a normal behavior. If so how can I understand which row is right?

Thanks in advance.