An event with the same ID already exists

I startup the Sentry server by docker-compose,I send events by postman with the same event ID.The server return me this message:An event with the same ID already exists (this is a event id)

But, when I start up the Sentry server by kubernetes,I send events by postman with the same event ID,there are no that message(An event with the same ID already exists (this is a event id)) response,but worker throw a exception like that:

SQL: INSERT INTO “sentry_eventmapping” (“project_id”, “group_id”, “event_id”, “date_added”) VALUES (%s, %s, %s, %s) RETURNING “sentry_eventmapping”.“id”
06:40:30 [INFO] sentry.events: duplicate.found (project_id=7L model=u’EventMapping’ group_id=7963L event_uuid=u’a4ee702788f24872a05850ee6c161d76’)
Traceback (most recent call last):
File “/usr/local/lib/python2.7/site-packages/sentry/event_manager.py”, line 613, in save
EventMapping.objects.create(project=project, group=group, event_id=event_id)
File “/usr/local/lib/python2.7/site-packages/django/db/models/manager.py”, line 157, in create
return self.get_queryset().create(**kwargs)
File “/usr/local/lib/python2.7/site-packages/django/db/models/query.py”, line 322, in create
obj.save(force_insert=True, using=self.db)
File “/usr/local/lib/python2.7/site-packages/django/db/models/base.py”, line 545, in save
force_update=force_update, update_fields=update_fields)
File “/usr/local/lib/python2.7/site-packages/django/db/models/base.py”, line 573, in save_base
updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
File “/usr/local/lib/python2.7/site-packages/django/db/models/base.py”, line 654, in _save_table
result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
File “/usr/local/lib/python2.7/site-packages/django/db/models/base.py”, line 687, in _do_insert
using=using, raw=raw)
File “/usr/local/lib/python2.7/site-packages/django/db/models/manager.py”, line 232, in _insert
return insert_query(self.model, objs, fields, **kwargs)
File “/usr/local/lib/python2.7/site-packages/django/db/models/query.py”, line 1514, in insert_query
return query.get_compiler(using=using).execute_sql(return_id)
File “/usr/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py”, line 903, in execute_sql
cursor.execute(sql, params)
File “/usr/local/lib/python2.7/site-packages/raven/contrib/django/client.py”, line 112, in execute
return real_execute(self, sql, params)
File “/usr/local/lib/python2.7/site-packages/django/db/backends/util.py”, line 53, in execute
return self.cursor.execute(sql, params)
File “/usr/local/lib/python2.7/site-packages/django/db/utils.py”, line 99, in exit
six.reraise(dj_exc_type, dj_exc_value, traceback)
File “/usr/local/lib/python2.7/site-packages/django/db/backends/util.py”, line 53, in execute
return self.cursor.execute(sql, params)
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/decorators.py”, line 80, in inner
raise_the_exception(self.db, e)
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/decorators.py”, line 78, in inner
return func(self, *args, **kwargs)
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/decorators.py”, line 22, in inner
return func(self, *args, **kwargs)
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/decorators.py”, line 101, in inner
six.reraise(exc_info[0], exc_info0, exc_info[2])
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/decorators.py”, line 94, in inner
return func(self, sql, *args, **kwargs)
File “/usr/local/lib/python2.7/site-packages/sentry/db/postgres/base.py”, line 39, in execute
return self.cursor.execute(sql, params)
IntegrityError: IntegrityError(‘duplicate key value violates unique constraint “sentry_eventmapping_project_id_eb6c54bf8930ba6_uniq”\nDETAIL: Key (project_id, event_id)=(7, a4ee702788f24872a05850ee6c161d76) already exists.\n’,)
SQL: INSERT INTO “sentry_eventmapping” (“project_id”, “group_id”, “event_id”, “date_added”) VALUES (%s, %s, %s, %s) RETURNING “sentry_eventmapping”.“id”
06:40:30 [INFO] sentry.events: duplicate.found (project_id=7L model=u’EventMapping’ group_id=7963L event_uuid=u’a4ee702788f24872a05850ee6c161d76’)
06:40:30 [ERROR] sentry.errors.events: process.failed.empty (cache_key=u’e:a4ee702788f24872a05850ee6c161d76:7’)

I want to know what cause that,could you help me?
This is not very important,because event id always different,I am curious.

By the way,I want to contribute my kubernetes deployment file to Sentry Project,can I?