My Contacts are gone from my iPhone?

Okay, literally, all of my contacts are all gone like what the eff just happened? Like when I opened my Messages all I see are their numbers… And I looked on my contacts app and there's nothing in it… Its pissing me off right now >.< I have a ton of numbers and I don't want to like add them all over again thats too much

anyone can help? That will be great.

Added (1). Nope, it's not jailbroken nor I leaned it on someone… It just happened I don't know why and now my contacts are gone

Is it jailbroken? If it's not, bring it to the apple store and ask for help.
Do you have backup? ICloud?
Did you leand your phone to someone recently? They could have deleted all your contacts as a joke or something.

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