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WHMCS\Exception\Application\InstallationVersionMisMatch: Database version '8.2.0-release.1' does not match file version '7.7.1-release.1' in /home/users/mazmedia/www/wh.mazmedia.de/vendor/whmcs/whmcs-foundation/lib/Application/ApplicationServiceProvider.php:0
Stack trace:
#0 /home/users/mazmedia/www/wh.mazmedia.de/init.php(0): WHMCS\Application\ApplicationServiceProvider::checkVersion()
#1 /home/users/mazmedia/www/wh.mazmedia.de/cart.php(0): unknown()
#2 {main}