When he told you to stay off your phone twice on the same day during your break, he may have simply been trying to get some kind of reaction out of you.
He may be the kind of guy that just likes the attention and will mess with you in order to get it.
The fact that he said this doesn’t indicate that he knows that you like him nor that he is giving you mixed signals.
The next time that you are at work or on break, observe how he goes about interacting with your other coworkers.
There is a good chance that you will notice that he has this kind of playful behavior with others as he attempts to get their attention as well.