How do I find an old version of Direct TV app that works with IOS 12 on my IPAD, the lastes IOS the Ipad will support?

How do I find an old version of Direct TV app that works with IOS 12 on my IPAD, the lastest IOS the Ipad will support?   It worked yesterday, but today it says I need to download a new version of Direct TV App.  But when I try, it says it will only work with IOS 14 or higher.  I try to download IOS 14, but my Ipad says my IOS up to date at 12 -- the last version works with my old ipad.  So how do I get an older version of Direct TV app that works with IOS 12, like it did just yesterday.  Thanks.