There are numerous websites like listed below which generates spam activities on your website, and may completely mess up with Google analytics report to addup to the number of daily visitors which are completely false users.
Login to google analytics,
go to Acquasition-> All Trafic -> Referrals
Copy the name of spaming website, as shown in above image, for example floating-share-buttons.com
and click on “Admin” tab as shown in above image at top right,
As shown in above image, in Admin tab, check for “VIEW”->All website data -> Filters
and click “New Filter” tab, inside this, “Create New Filter” , add the filter name as you want
in “Filter Name” , click “Filter Type” as “Custom” , set “Filter Field” to “Campaign Source”
in the “Filter Pattern”, paste the URL we copied above, and click “Verify this filter”
If there is a spam activity from same website, you should see something like below,
Now Click “Save” and DONE 🙂