Works fine here among my MacBook and my iPad and iPhone X. . . all directions between all three. What kind of desktop are you referring to? How about from the iPhone to desktop?
Question... where does money sent - via Apple Pay Cash - get deposited? Into a bank account?? On to the recipients credit card??
TIA.
Thanks for checking out.
I am not alone with this problem, it’s been going on for three months.
https://discussions.apple.com/thread/8079251?start=195&tstart=0