Who called from 2102808487

This number calls me and when i answer they wait 10 seconds or so and then say goodbye and hang up on me. i have no idea who is calling or why.

kepts calling I am on the do not disturb list

I havea received five calls today from 210-280-8487, and all were hangup calls. They may be from a Verizon subsidiary in Texas. When I return the call I get a message to recheck my no.

Have received several calls from this number.  I usually just ignore them because they don't leave a message or identify themselves.  The one time I did pick up the phone there was about 15 seconds of silence and then I hung up.

Hung up on 3rd ring. Caller ID says San Antonio, TX. No idea who this is since they hung up too quickly.