Trouble with Credit Usage for LinkedIn Contact Finder - Requesting Refund or More Credits

Hi everyone, I just bought the 2000 credit plan and started using the find LinkedIn companies + Find people queries. The results came back with 1683 people and I chose to get their emails and linkedin info - i know I am a n00b to this, but it ended up using up all of my credits in less than 15-20 minutes and gave me less than 150 unique contacts back (some with questionable work emails at at that). Is there anyway I can either get a refund or perhaps more credits ? it also wasn’t very clear how the credit system works… maybe I should have done more research beforehand. I appreciate any help that you guys can provide!