@iluvli - assuming that you have not accidently deleted all of your cards and are refering to the standard full screen scenes supplied by Totem I can think of three possibilities

1) You have disabled all of your cards on the "My Collection" page.

2) You have disabled either all collections or all levels of eroticism via the iStripper settings page.

3) You have disabled every clip via each of the girls details clip list page.

Of these the first is the most likely and would be result in the cards being partially greyed out on "My Collections". If so just reenable them. The second is rather less likely but if it is the cause go to the Settings page via the cog wheel icon in the GUI's title bar and ensure that at least some level of eroticism is allowed when playing scenes (note that there are two sets of controls, the first is for desktop mode and the other below that for full screen scenes)

UPDATE:

Another possible explanation is that you are trying to play a specific scene that requires a particular type of clip and that none of the cards in your collection have this kind of clip. As far as I can remember only one of Totem's own scenes has any such restriction and that is to "bikinis". If this is the reason for your problem then simply play different scenes.