phone calls with no one on line when picked up.

IRS scammers called twice at 8:34 and 8:35 am leaving a robo voicemail on my cell. The grammar is bad. It sounds like Asian grammar in my opinion. So it's probably from overseas using the spoofed (325) 205-1850, San Saba, TX number.
According to the WhitePages app, it's an AT&T cell number.
I just got a 3rd call and second voicemail at 8:44 am while writing this comment.
This is the exact transcript of the voicemail.

Hello,
This call is officially a final notice from IRS, Internal Revenue Service. The reason of this call is to inform you that IRS is filing lawsuit against you. To get more information about this case file please call immediately on our department number, (325) 205-1850. I repeat, (325) 205-1850.
Thank you.

I called AT&T cellular and filed a report since Whitepages lists the number as an AT&T cellular line.
I realize I thought the number was spoofed, but their voicemail asks you to call back the same number they called from. So it's unlikely to be spoofed unless they can rerouted the call to another number.

Got a call from this same number with most of the same message about "IRS is filing lawsuit against you." They must have started playing the message during my voicemail greeting because it sounds like the recording started while the above transcript was in progress.  Needless to say, this call doesn't sound legitimate.

Got the same lame call. This scam is almost as bad as receiving a fax from a Nigerian prince wanting you to hold his fortune for a small investment.