It seems to be the latest thing that scammers like to do. They SPOOF the first six digits of your phone number and continue to phone doing this (each time changing the last four digits each time). This 713-503-4321 called me today and I did not answer. No voicemail was left, so I am pretty certain that it is just a scammer once again taking liberties with calling. No problem. I have several 713-503-xxxx on my reject list. This will be just another one. Just be aware that the scammers will often SPOOF the first six digits of your phone number because they are thinking that you will answer it (as you might think it is someone you know. Don't fall for it. Let it go to voicemail. If they don't leave a voicemail, then it must not be important.