According to https://www.suitecrm.com/forum/suitecrm-7-0-discussion/4456-session-time-out-increase, this is an issue in SuiteCRM. This could be fixed by editing
/opt/bitnami/php/etc/php.ini and setting these values:
session.cookie_lifetime = 0
session.gc_maxlifetime = 14 400
Then, could you please restart php and apache services in your server by executing the following command?
sudo /opt/bitnami/ctlscript.sh restart php-fpm
sudo /opt/bitnami/ctlscript.sh restart apache
Hope it helps.
Javier J. Salmerón