U-verse unavailable at this time

Make sure all connections are tight.

Unplug all boxes from power.

Plug the gateway back in and wait for normal operations.

Plug the WAP back in and wait for normal operations.

Plug the DVR back in and wait for normal operations.

Plug the receivers back in and wait for normal operations.

Did the wireless receiver change positions? Keep in mind that it can't be too far from the WAP, similar to how a laptop has to be so close for WiFi.

I followed your instructions exactly. I do not have a separate DVR. Still says it’s not available at this time.

any suggestions other than to call support again?

The DVR is the largest box AT&T provides which is connected to a TV.

The smaller ones are receivers.

I'm on the phone now with technical support after talking to att support for 40 minutes. I hope they can fix it. 

Again, I have a gateway, WAP, and a receiver, nothing else, and I've never had an additional box.

Am I misunderstanding?

What service level do you have? (U-Family, U-200, etc.)

What is the model number of your receiver?

U-200 and ISB 7005

I held on for technical support for an hour and a half and then hung up. This is so frustrating!

If you have U-200, then you have been eligible for DVR service; the ability to record shows and play them later; to pause, rewind and/or fast forward live TV.  In order to do this, one of the receivers in your home must be a DVR receiver.  A DVR can never be wireless, it must be connected to the Gateway via Coax or Ethernet.

Your configuration is confusing because we've never seen a configuration with just a WAP and a wireless receiver.  We're not sure how such a thing is even supposed to work.

How long have you had U-200?  Have you ever had the DVR features?

If I have needed more equipment why has Uverse and the DVR function worked at this location for the past dozen years? 

If the DVR function has worked all this time, then something is not as you have presented it.

You could have a DVR that is not connected to a TV.  This is something that some people do if they cannot run a cable to where their TV is.  Please check again to make absolutely sure there isn't another box connected via Coax or Ethernet.