The Indian guys are calling from the actual number now; 800-811-8181 which is the correct number for them to be using, NOT the 800-811-1877 which they were using by mistake.
Here's what I saw on another post:
"I got a call this afternoon from this number.  The Indian guy said he was from Reliance Protectron and tried to sell me on a home alarm system.  They don't listen and even when I say no he keeps on talking.  Then they keep calling back."

I did some digging on the call and it's some Indian guy trying to sell alarm systems but, when I call the 800 number, it's a totally different company that isn't in the alarm business.
The number that called me is being spoofed or faked and the real owner of the number is not making these calls.

Must be some idiot call centre in India somewhere (judging on the accent) that goofed up.
If you get more details on these guys please post it here.

I have the exact same problem :/

Calls my house almost every single day and everytime I pick up there's nobody on the other end.

This company constantly calls and hangs up and when I call back no one ever answers. Adequasys I think??