Cron Not Working

I I have a crontab set up exactly as the instructions said, I also setup the .timer and .service but it doesnt seem to be working, All my other PHP crons work fine but it only seems to be nextcloud that doesnt want to work. I have */5 * * * * /usr/bin/php7.4 -f /var/www/kian/nextcloud/cron.php set on my cron running under the www-data user, but it still isnt working. Im not sure as to what is wrong. If someone has any ideas whats wrong please comment.