Cron Jobs

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I got the solution to this by doing
define(‘ALTERNATE_WP_CRON’, true);
and my backup was successful
but after 1 day, it started appending
https://www.mydomain.com/?doingcron=8387539920/ something to my url

i removed the line define(‘ALTERNATE_WP_CRON’, true);
and now again i can’t take backup. ??
what to do? kindly help!