There may be a time where you want to have a fresh dashboard without the stats and logs. A case maybe a misconfigured NIC that may dump millions of DNS queries into the logs. Yup I have seen this happen. Whenever you need to reset the pihole stats and logs that display on the /admin dashboard, the following options will do the trick. As an option, the old database may be saved or deleted. If the database is excessively large, consider deleting it.
cd /etc/pihole sudo service pihole-FTL stop #sudo mv pihole-FTL.db pihole-FTL.db.old rm pihole-FTL.db sudo service pihole-FTL start