Continue taking flats does not work

I waited until 10:01 for the new SPG day and then I wanted to finish my flats. I unchecked the target with the light frames and only checked the target with the flats, dark, bias.

But when I press Resume Sequence I get this message. It is also strange that it says time remaining is 0 since there are 31 frames left to do.

What am I doing wrong here.
Thanks,
Dietmar