Update NC 14 Beta from NC 13 - Updater does not recognize PHP 7 as CGI/FPM

Any hint how to upgrade?

This version of Nextcloud requires at least PHP 7.0
You are currently running 5.6.32-nmm1. Please update your PHP version.

Server runs with PHP 7.1 as CGI/FPM on a shared host. Upgrades worked well before.