Repetition setting not working

I am trying to set a task to repeat weekly on mon, thurs and fri. I have done this before with other tasks and it worked fine and dandy. I am using Firefox.

But now, all I get is this repetition sign (two arrows in circle) next to the task, the task does not show up on any other day than monday of the present week.

What could I be doing wrong?

I have even specified 1week in the field "repeats every...", although it has not been necessary with my other weekly tasks.