feeling uneasy about teaching a student, should I block him?

I started teaching spanish part-time around a week ago on preply and I already have around 10 students! I have a growing demand, even though I've upped my prices to above $20.

My second ever student on the platform is a guy in my age range. He doesn't seem interested in the lessons, is always going on his phone, complaining about how spanish is hard and things like that. He's planning a trip to south america soon and I honestly think he is just trying to learn spanish to get with latinas. I always dread teaching him, specially since all of my other students are really motivated and we're always having good chats.

In addition to that, last lesson he made a flirty comment asking if he was my favorite student. I got awkward and just didn't know how to respond, because I am in a relationship and I'm not looking for anything at all apart from a student/tutor relationship or, at most, a friendship. I tried to laugh it off, but I'm still thinking about that and scared he will try to continue flirting during out next lessons.

I honestly don't feel comfortable teaching him anymore and I was wondering if it would be okay to block him. He still has a lot of lessons booked for this month. I'm scared he will try to find my profile or talk to me in some other platform.

I would really appreciate some guidance!