Can't save the sprint in Scrum board

[Екатерина Герасименко]

Hi! I can't put tasks into a sprint.

I move tasks to a sprint section, then click "start a sprint". I'm redirected to the board screen and there are no tasks on the board.

But when I come back to the backlog I see all the tasks I've chosen for the sprint are  back in the backlog! 

What am I doing wrong? 

[Jack]

Can you share an image of your backlog? My guess is that either you don’t have permissions to manage sprints so that the sprint button is grayed out or something isn’t mapped correctly on your scrum board. Have you been able to manage sprints in the past with this specific project?

[Екатерина Герасименко]

I found the answer. 

I manage multiple projects on one board and "sprints" should be enabled in all projects.

[Jack]

Yep that is a common snag. Multi-project boards can trip you up.