iTunes Shuffle is stuck on, and 2018 fixes don't work

It's unfortunate that you didn't mention what the fixes are that you tried, so my apologies if I'm repeating them.

In addition, having re-read your post a couple of times, I'm not clear exactly where your problem lies:

• • if you're paying Apple every month, that suggests that you're using Apple Music rather than iTunes
  • but if you do mean that in iTunes, your music is being shuffled and you can't turn that off, try the following:
    • on iTunes' top bar menu, tap the Controls option and select Shuffle from the menu and then select Off from the sub-menu
    • that's Controls/Shuffle/Off:

Notice the Shuffle icon in the Now Playing window (above the 4:44 time indication):

• • the light arrows on dark grey background tells you that Shuffle is on
  • when the arrows are dark grey, with no background colour, Shuffle is off