Update fails when Bing [Bot] was already added to the users table

Fatal error: in E:\phpBB-development\htdocs\phpBB-git\3.0\phpBB\includes\db\dbal.php on line 696

SQL ERROR [ mysqli ]

Duplicate entry 'bing [bot]' for key 'username_clean' [1062]

SQL

INSERT INTO phpbb_users [...]

BACKTRACE

FILE: includes/db/mysqli.php

LINE: 163

CALL: dbal->sql_error()

FILE: includes/functions_user.php

LINE: 250

CALL: dbal_mysqli->sql_query()

FILE: install/database_update.php

LINE: 1747

CALL: user_add()

FILE: install/database_update.php

LINE: 398

CALL: change_database_data()