Sea Trout Fan
Once you are logged in and ticked the little box to stay logged in you shouldn't see the data prompt thing again.
You need to be accepting cookies so that your computer etc knows not to keep allowing the pop ups.
My browser is set to always allow cookies and I have ticked the box to stay logged in. I still get that pop up every time.
I'm using an old iPad with an older version of i.o.s, so may be something to do with that.