We have moved our site from http to https now all Facebook share count gone away it is showing 0 for facebook.
Facebook Share Count
For Facebook Share, Like and Comment Count you need to add your old url in og tag.
<meta property="og:url" content="http://www.oldurl.com/" />
Go to facebook debuger tool (https://developers.facebook.com/tools/debug/) and press Scrap Again and you will find that all your old Facebook Share Count get transfered to your new URL.
For Google + and Linkedin you no need to do anything share count will transfer automatically for every post.