No one on the line when I picked up; ID said TMS, which according to my log is Total Merchant Services, usually calling from the 918 area code, known illegal robocaller

Yep, it's them, using a new number. They call simultaneously on two lines and if their patterns hold as in the past, they'll call every hour or so for a few days on both lines. I think this is called harassment.

This number called our business 3/21/16 & hung up when we answered

several calls from this TMS #  405  673-2378 over the pas week around 20 calls

First time they called and no one was there when I answsered.  Second time they called right back and I could hear loud background noise and the caller asked for the Owner.  Placed on hold until they got tired and hung up.