Cat-phishing, or fake identities is not a victimless crime and it can be really dangerous. You never know who when someone is actually posing as someone else.
never, ever give your personal information to the fake person
if you are not sure who the people actually are, don´T panic, just ask them certain info on who they are trying to be
if you know that the person is actually a fraud, contact
reverse lookup their profile images, meaning copy the image and paste it into a google search. if there are more than one photo, or even profile of that person