Error switching from custom report page to all page rollup

WARNING: /var/www/html/piwik/core/Piwik.php(138): Notice - A non well formed numeric value encountered - Matomo 3.13.6 - Please report this message in the Matomo forums: https://forum.matomo.org (please do a search first as it might have been reported already) (Module: CustomReports, Action: getCustomReport, In CLI mode: false)

i was in custom reports on one site, and i clicked the sites drop down to switch to the all-sites rollup site and i got this error filling my screen.

Hi Cory,

Please make sure your Matomo and plugins are at the latest version, let us know if you can still reproduce the error.

Thanks