The booking add-on is available for download at the Moodle plugins database (https://moodle.org/plugins/pluginversions.php?plugin=mod_booking) for all branches from 2.0 to 2.5 but AMOS only has the strings for translation from 2.0 to 2.3
Please help.
Correct. The add-on has some issues with the strings file (see the recent comments at its Plugins page) so the strings could not be translated. Meanwhile, just translate the latest available version in AMOS. Its strings will be used in all higher versions by default.
