Guy's Behavior

Weird question?

i texted my classmate if he got a notification about the assignment we need to do. We have a few classes together we are polite to each other. He respond my text by sailing if I’m with (random Male classmate name). I answer by saying no, I’m not with him. Last time I check he was with his girl and his friend. He answer “why are you lying?”. I reply huh?

since I’m actually confused. He keeps replying :”since when” . I was so confused that I stop talking to him. Any advice on the sudden weird behavior?

Weird question?
Post Opinion