Do ANY of the boxes allow rewind of live TV easily, regularly, and preferably for at least two channels at once?

I was recently forced to ‘upgrade’ from my Tivo because Xfinity doesn’t allow cable cards any more.  They are renting a wireless box (all they had available) to me that does practically nothing.  I usually can't rewind live TV because there's no buffer/memory there!  I wake up in the morning, turn on the TV so I can rewind the last 30 minutes of news to watch, but no, the box has done NOTHING overnight, so it's all empty.  OK, so I see that it's finally starting to record the news.  While waiting for the recording to build up, I go to watch a recorded program, then return to watch the news recorded over the last half hour, and it's empty again!!!!  What am I doing wrong?  This is primitive.  My Tivo from a quarter-century ago was dramatically better than what Xfinity offers today.

Am I pushing the wrong buttons on my remote?  What button do I hit to be able to go back and review the last 30 minutes when I first turn my TV on?  And is this unit really only one tuner?  On my old, outdated Tivo, I would have a half hour buffer/memory saved up on 6 different channels.  Does Xfinity have even one DVR that offers services from this century rather than the last one?  If so, which box is it and how do I get it?