This happened to me last year, well it's happened to me several times in fact.
On the last occasion though, myself and a bird I'd been eyeing up for months at work decided that after all this time we'd also been fancying eachother so we exchanged numbers and agreed to meet.
She assured me she was single. Great I thought, but, everyone knows that Thai girls always say that.
Anyway a couple of weeks later I recieve phone calls in the night, and when non-english speaking Thai guys call you up, the scenario is identical, it goes something like this:
(***sound of phone***)
ME: Hello ?
BOYFRIEND OF GIRL: Hallo kap?
ME: Yes, hello.
BOYFRIEND OF GIRL: Hallo kap?
BOYFRIEND OF GIRL: Hallo kap?
ME: Yes, hello.
BOYFRIEND OF GIRL: Hallo kap?
BOYFRIEND OF GIRL: Hallo kap?
ME: Yes, hello.
BOYFRIEND OF GIRL: Hallo kap? (in Thai) I am the boyfriend of __________ .
ME: Really? OK then no problem, bye.
BOYFRIEND OF GIRL: Hallo kap?
ME: Yes, hello.
BOYFRIEND OF GIRL: Hallo kap?
BOYFRIEND OF GIRL: Hallo kap?
ME: Yes, hello.
BOYFRIEND OF GIRL: Hallo kap?
Then I hang up cos that is all they say. You should try it one day, it can be amusing.