Solitaire is no longer able to support Landscape mode on iPhone devices. 
 
Solitaire can still be played in Landscape and Portrait mode on iPad devices.
 
If you're playing on iPad and your screen is not automatically rotating on its side, the orientation/screen lock is likely enabled. 
 
To turn off the orientation/ screen lock for iPad screen will auto-rotate:
  1. Open Control Center
    • iPads running iOS 12 or later: from the top-right corner of the screen, drag your finger mid-screen
    • iPads running iOS 11 or earlier from the bottom center of the screen, drag your finger mid-screen
  2. Locate the lock with the circular arrow around it and tap it to turn Portrait Orientation Lock off.
Apple Support Articles:

 

♥️♣️♦️♠️

Don't see what you're looking for? Let’s talk about it. Select Contact Us in the upper-right corner or message button at the bottom.