Error updating sessions table

DEBUG MODE

SQL Error : 1062 Duplicate entry 'viewtopic.php?download=4758&f=35&t=528&_f_=35x&_t_=528x' for key 'session_page'

UPDATE phpbb_sessions SET session_time = 1788985830, session_start = 1788985830, session_page = 'viewtopic.php?download=4758&f=35&t=528&_f_=35x&_t_=528x' WHERE session_id = 'bee14f2ca7d02822b0451f25a936a304'

Line : 556
File : sessions.php