I’ve used the Fastor theme in my online shop, on Opencart 18.104.22.168 plate form, Now I want to upgrade the version of Open Cart to OpenCart 22.214.171.124, what’s the way?"
If you are a orginal theme purchaser from themeforest then you:
Check the theme documentation hopefully you will get necessary support. If you have still problem with the theme then The best way to get the support is Contact your purchased Theme Author. Contact Author Support and let them know.
Otherwise Envato Studio is a freelancer platform. For doing this job I would certainly recommend one of the Opencart experts at Envato Studio. They’re really good and surprisingly affordable.
You have to first upgrade the ver. of opencart and than re-install the theme.