Redmine

I have select 7 issues and change their assignment.
Assignment have been changed, but browser stayed on empty page with next link:
http://tasks.sloboda-studio.com/issues/bulk_update?back_url=%2Fprojects%2Fsoftsource%2Fissues%3Fc%255B%255D%3Dtracker%26c%255B%255D%3Dstatus%26c%255B%255D%3Dpriority%26c%255B%255D%3Dsubject%26c%255B%255D%3Dassigned_to%26c%255B%255D%3Destimated_hours%26c%255B%255D%3Dupdated_on%26f%255B%255D%3Dstatus_id%26f%255B%255D%3Dassigned_to_id%26f%255B%255D%3D%26group_by%3D%26op%255Bassigned_to_id%255D%3D%253D%26op%255Bstatus_id%255D%3Do%26set_filter%3D1%26utf8%3D%25E2%259C%2593%26v%255Bassigned_to_id%255D%255B%255D%3D4&ids%5B%5D=443&ids%5B%5D=599&ids%5B%5D=640&ids%5B%5D=663&ids%5B%5D=705&ids%5B%5D=737&ids%5B%5D=743&issue%5Bassigned_to_id%5D=37

Server Environment:
ruby-2.0.0-p353 [ i686 ]
rails 3.2.11
mysql Ver 14.14 Distrib 5.5.37, for debian-linux-gnu (i686) using readline 6.2

Client Environment:
chromium-browser Version 34.0.1847.116 Ubuntu 12.04 (260972)