I'm guessing you meant "turning you down"? If someone says they are "seeing someone at the moment" that means they are taken, or dating someone, and in turn can't date you unfortunately Hope this helps!

Yes. They mean they have a partner and aren't interested to be with you. The right way to phrase your question is "is he turning me down"

It’s a turn down gesture

Unfortunately yes, if that person is seeing someone that means they're dating and this automatically turns you down. :(

Hi, Yu Wun! atm = at the moment To see someone = To date someone or meet (with) someone (for example, seeing a doctor).