Hello, i had this problem for a few days. When i go through my cards for the day and come a cross already learned once that i forgot i press the button to repeat them in under 10 minutes. But as soon as i press this button the card disappears and the next day Anki presents me the same card and when i press the 10 minutes button the same thing happens. When i notice it due to the numbers at the bottom, i press the redo button and press the 10 minutes again, than everything works normal.
Sry for the broken englisch and thank you very much