I can not unlock my phone. I did not lock it or anything. Can someone help me?

What might "unlock" mean?

• Forgot passcode? If you forgot the passcode on your iPhone, or your iPhone is disabled - Apple Support
• Remove Activation Lock (from a previous owner)? Turn off Activation Lock - Apple Support
• Unlock from a cellular carrier? Only the original cellular carrier may do that if they choose to do so.
• Something else?

Locked how? Are you saying that you cannot use the passcode to get into the iPhone? Is it Activation Locked? Is it locked to a carrier and you wish to use another one? Describe what you mean, what you are seeing, and if there is an error on the screen, what is the exact text.