called me 20 times today and they hang up.

I got a call from this number today.  I have received at least 10 calls from numbers I didn't recognize today.  Most have area codes from Mexico.  This one is from California but I didn't answer it.  It is not my daughter's number and I don't know any one else there.  Very strange.  Have never received do many calls in one day.  Don't know where they got my number.  It's my cell number.