They're probably not lost. In Contacts, go to Menu and then tap Contacts To Display. Tinker in these setting and you'll figure out which list is the right one and which ones you want to see. You can see Google contacts, Phone contacts, SIM contacts, All contacts, and other accounts you have. While you're in there, make sure which accounts you have set to sync.
Other solution try Samsung recovery program,
http://www.androidphonesoft.com/resources/recover-deleted-contacts-from-samsung-galaxy-s4.html
hope it helps!
My little boy deleted some of very important contacts on my Galaxy S5 when playing with the device. I am guessing is there any way to get these deleted contacts back? Any suggestion and input will be great appreciated.
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