I am on Magento 2.1.7 and whenever i refresh my page cache in the System - Cache Management - Flush Magento Cache... It crashes the website momentarily. After about 5 minutes the site is able to be refreshed and will act normal. While the site is down the error appears...


An error has happened during application run. See exception log for details.
Any idea on what may be causing this?
Cheers,
Thanks for all the help.