Seasonal Trial unavailable - "The Trial has finished for the season"

When I try do the seasonal Trial (Mud & Guts) I can’t enter the event because the Find Team option is locked with the following error message:

The Trial has finished for the season

I’m playing on PC and it’s the second week in a row this has happened.

Still suffering from this, hoping to see a solution before the end of the season.

In case anyone ever comes across this error via Google, I fixed this problem by changing my region in the Windows 10 system settings. I assume the region needs to be the same in Windows and XBL and that wasn’t the case for me.