Duplicate key error during Celery task

[ghost]

  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/celery/app/trace.py", line 240, in trace_task
    R = retval = fun(*args, **kwargs)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/celery/app/trace.py", line 438, in __protected_call__
    return self.run(*args, **kwargs)
  File "/var/www/tracpro/source/tracpro/contacts/tasks.py", line 35, in push_contact_change
    sync_push_contact(org, contact, change_type, [region_uuids, group_uuids])
  File "/var/www/tracpro/env/src/dash/dash/utils/sync.py", line 36, in sync_push_contact
    contact.save()
  File "/var/www/tracpro/source/tracpro/contacts/models.py", line 207, in save
    contact = super(Contact, self).save(*args, **kwargs)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/base.py", line 734, in save
    force_update=force_update, update_fields=update_fields)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/base.py", line 762, in save_base
    updated = self._save_table(raw, cls, force_insert, force_update, using, update_fields)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/base.py", line 827, in _save_table
    forced_update)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/base.py", line 877, in _do_update
    return filtered._update(values) > 0
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/query.py", line 580, in _update
    return query.get_compiler(self.db).execute_sql(CURSOR)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 1062, in execute_sql
    cursor = super(SQLUpdateCompiler, self).execute_sql(result_type)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/models/sql/compiler.py", line 840, in execute_sql
    cursor.execute(sql, params)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/utils.py", line 98, in __exit__
    six.reraise(dj_exc_type, dj_exc_value, traceback)
  File "/var/www/tracpro/env/local/lib/python2.7/site-packages/django/db/backends/utils.py", line 64, in execute
    return self.cursor.execute(sql, params)
IntegrityError: duplicate key value violates unique constraint "contacts_contact_uuid_key"
DETAIL:  Key (uuid)=(19a798b8-0aa2-46f4-b617-b189a3e0adf7) already exists.