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WHMCS\Exception\Application\InstallationVersionMisMatch: Database version '8.9.0-release.1' does not match file version '8.10.1-release.1' in /home/azbilling/public_html/billing/vendor/whmcs/whmcs-foundation/lib/Application/ApplicationServiceProvider.php:0
Stack trace:
#0 /home/azbilling/public_html/billing/init.php(0): WHMCS\Application\ApplicationServiceProvider::checkVersion()
#1 /home/azbilling/public_html/billing/index.php(0): unknown()
#2 {main}