Now that you stopped it for future occurrences is time to clean the affected data. Unfortunately, there is no way to delete this records but you can use Segments to remove them from your reports.
1 Go to the Reporting section in your Google Analytics.
2 In the lateral bar, expand Acquisitions > All Traffic and Select Referrals.
3 In the main board Click on +Add Segment.
4 Click on New Segment.
5 Select Conditions Below Advanced.
6 Set filter as Exclude. Change Ad Content for Medium and contains for exactly matches and type and select referral in the text box.
7 Click on AND
8 Change Ad Content for Source and contains for matches regex and paste this expression
social-buttons.com|simple-share-buttons.com|free-share-buttons.com