Issue with Email Enriching Consuming Credits on New Leads

Hi can someone please help me with something! I had a sheet with 50 leads in it that I enriched with emails, to test the leads. I then went to add 450 more leads to go through and see if they were good but then the email enriching automatically ran for the 450 new leads and blew through the majority of my new credits. Is there anyway I can undo this or maybe just filter out the leads from the new 450 that aren't relevant and get some credits back?