I have Uniden Model DWX337. And I can't get the base to expand.?

My brother had multiple sets of this phone but has moved and I have acquired one of the bases and a 2nd phone/cradle.

But no matter what I do I cannot get the 2nd phone to connect to the base. I searched online and many said it's cause the base has too many phones on it.

But the only thing I saw to unpair phones required the phones, which I don't have. Someone did suggest a full on reset of the phones.

So I did that. I unplugged the bases and removed the batteries from the phones. I actually left them unplugged over night as it's a new line that I haven't given the number out for yet, so I was not worried about missed calls. I plugged them all back in this morning and both phones said searching. I placed the original on the cradle and it quickly paired itself. But the 2nd one still says searching.

I even bought a third phone off ebay thinking it was the phone and that one is doing the same thing.

I have also pushed the find button on the base while pushing the pound button on the phone as that was another way I read it could be paired and that didn't work either.

And I pushed the star and pound keys with the battery out, while plugging the battery back in as that was suppose to reset the phone so it could then be paired... that came straight out of the online user manual and it still didn't work.

What can I do to get these phones to work?

I would appreciate any suggestions that could lead to a solution as I contacted Uniden twice and got no response. 

Thanks