Crontab error after upgrade from 14 to 15

after upgrade from 14 to 15 the apply tab appears when clicked I get the error:
[code]

1. 1. 1. There was an error during reload: Unknown Error. Please Run: fwconsole reload --verbose

Unknown Error. Please Run: fwconsole reload --verbose
[/code]

when the stated command is ran on console it get:
[code]
Reload Started

In Cron.class.php line 126:

[Exception]
Cron line added didn't remain in crontab on final check. Check /tmp/cron.error for reason.

Exception trace:
() at /var/www/html/admin/libraries/BMO/Cron.class.php:126
FreePBX\Cron->addLine() at /var/www/html/admin/libraries/BMO/Cron.class.php:226
FreePBX\Cron->add() at /var/www/html/admin/libraries/Builtin/UpdateManager.php:242
FreePBX\Builtin\UpdateManager->updateCrontab() at /var/www/html/admin/libraries/Console/Reload.class.php:822
FreePBX\Console\Command\Reload->installCrons() at /var/www/html/admin/libraries/Console/Reload.class.php:371
FreePBX\Console\Command\Reload->reload() at /var/www/html/admin/libraries/Console/Reload.class.php:90
FreePBX\Console\Command\Reload->execute() at /var/www/html/admin/libraries/Composer/vendor/symfony/console/Command/Command.php:255
Symfony\Component\Console\Command\Command->run() at /var/www/html/admin/libraries/Composer/vendor/symfony/console/Application.php:960
Symfony\Component\Console\Application->doRunCommand() at /var/www/html/admin/libraries/Composer/vendor/symfony/console/Application.php:255
Symfony\Component\Console\Application->doRun() at /var/www/html/admin/libraries/Composer/vendor/symfony/console/Application.php:148
Symfony\Component\Console\Application->run() at /var/lib/asterisk/bin/fwconsole:163

reload [--json] [--dry-run] [--skip-registry-checks] [--dont-reload-asterisk]
[/code]

the output of /tmp/cron.errror is:
[code]

"-":22: bad day-of-month
errors in crontab file, can't install.
"-":22: bad day-of-month
errors in crontab file, can't install.
"-":23: bad day-of-month
errors in crontab file, can't install.
"-":23: bad day-of-month
errors in crontab file, can't install.
[/code]