In last week’s first question, Black’s only drawing move is Rh1!, followed by Rh6+. Everything else loses with best play.
Instead, I played Rf1?, but, a few moves later, was offered a second chance.
White, with many winning moves to choose from, has just played Ke7-d7?, which enables me to draw with, and only with, Ra2!
After Rd2+, though, I lost a few moves later.
My mistake in this game was that I was only thinking about vertical checks, not horizontal checks.
This game taught me an important lesson about rook and pawn endings. It might help you as well.