Captain01012 My PHP is already 7.3 but why showing this error? flarum/core[v1.2.0, ..., v1.2.1] require php >=7.3 -> your php version (7.2.34) does not satisfy that requirement.
luceos Captain01012 sometimes php versions are different between the command line (cli/ssh) and the website. You can probably configure the commandline php version in your control panel or access another php version using a different binary (eg php74 composer ...).
Valeyard Are you on shared hosting? Select PHP 8.0 or 8.1 in the version selector in the control panel.
Captain01012 Valeyard I have already changed my PHP version to 7.3 but not working but PHP file shows 7.3
