Who called from 5712811499

Got a call from this number that says "I can't hear you"...then when you call back its some recorded message trying to give you a "free" gift card or something.

Waste of time - do not answer or call back.

i keep getting calls from this number that say "hello, hello?" and then hang up

Multiple calls from this number...they say, "hello, hello" and then hang up.