Who called from 5024101375

i was busy cleaning my room then my phone rang.
i picked it up and it was quiet for about 12 seconds, then they hung up.
i kept on saying "hello" but no noise whatsoever.
so i called it back and i got a busy tone. so i left it alone.
an hour later i called back and i got a message saying,
"the number you called does not exist, check your number and call again"
i was like "??? how does it not exist? it just called me!?"

so i called again another hour later and i got
"the number you caled could not be completed for dial, call back again later"

eh...
ill try again later i guess

Keeps calling and not leaving a message.

Calls and leaves no message.  Who are they????

I keep receiving calls from this number numerous times throughout the day without anyone answering or leaving a message. When I attempt to call the number, all I get is a busy signal. This has got to stop immediately.

They just called me too and when i call back it says the number you have reached is not in service..weird!