if it's the same server, just run upgrade will do:
/usr/local/lsws/admin/misc/lsup.sh -f -v 5.0.9
if on different server, you can transfer the license:
https://www.litespeedtech.com/support/wiki/doku.php/litespeed_wiki:licenses:transfer-or-release-a-license
license is license, version is...