Uptime Monitoring reports false positive

Hi Gurus,

I received two emails today indicating that the uptime monitor detected my website was unavailable from 3:21 to 3:36 pm today. When I contacted my web hosting company, they investigated and could not locate any evidence that the website was unavailable. The only problem the host technicians could find had to do with the following file:
/wp-admin/admin-ajax.php. I'm wondering if this file causes problems for others or just me?

Is there something I can do to improve the performance of the uptime monitor to ignore these kinds of false positives?

Thanks Kindly,