logwatch not sending emails, not doing anything

I'm running centos 7 with logwatch-7.4.0 and logwatch doesn't seem to be working at all. I've installed it and set it up exactly the same way as other machines I have. this is what happens when I run it manually:
Code:logwatch --detail Low --debug medium --output mail --mailto <my email> --service http --range today

export LOGWATCH_DATE_RANGE='today'
export LOGWATCH_OUTPUT_TYPE='mail'
export LOGWATCH_FORMAT_TYPE='text'
export LOGWATCH_TEMP_DIR='/var/cache/logwatch/logwatch.HrLAWVqV/'
export LOGWATCH_DEBUG='5'
export http_ignore_error_hacks='0'
export http_user_display='0'here is my /etc/logwatch/conf/logwatch.conf file
Quote:

LogDir = /var/log TmpDir = /var/cache/logwatch Output = stdout Format = text Encode = none MailTo = <me@my-email.com> MailFrom = Logwatch Range = yesterday Detail = Low Service = All Service = "-zz-network" Service = "-zz-sys" Service = "-eximstats" mailer = "/usr/sbin/sendmail -t"

this file is exactly the same as the logwatch.conf file in my other centos 7 machines and they work fine. I've also tried '--range all' but still nothing.
nothing happens in /var/log/maillog and nothing happens in /var/log/messages.
scratching my head and i'm baffled, thanks for any pointers