Error in creating a backup

I encountered an error when running the varbase updater and reached the creation of backup process.

PHP Parse error: syntax error, unexpected ':', expecting '{' in /Users/rakera/Sites/devdesktop/varbase/vendor/symfony/polyfill-php80/bootstrap.php on line 23

Parse error: syntax error, unexpected ':', expecting '{' in /Users/rakera/Sites/devdesktop/varbase/vendor/symfony/polyfill-php80/bootstrap.php on line 23
Drush command terminated abnormally due to an unrecoverable error. [error]
Error: syntax error, unexpected ':', expecting '{' in
/Users/rakera/Sites/devdesktop/varbase/vendor/symfony/polyfill-php80/bootstrap.php,
line 23

I have not been able to proceed pass this stage. Not sure if this is a bug or not. I tried different installation of varbase, i.e. installing from composer directly and also using lando but the same error occurred.

Really need guidance on this.

Thanks.