they called my mom who's 75 year old & told her to pay in  otherwise her power will be shut off in 45 minutes.They claimed that they are from Excell Energy Center.

i told the guy that i reported to police already, told him to f up.

This is a scam number.  They are looking to scare you into giving them money.  If you call the number back, they answer disconnection center.  DO NOT give them money!