I checked your Same Station Exit page, but it didn’t quite apply to me- I have a travelcard on my Oyster, and only a few pence of PAYG credit left.
I touched in at a DLR station without gates, then needed to exit without making a journey. I tried a few times, after various intervals, to touch out, but each time, the reader always showed “entry”. In the end, I went one stop, touched out, and then touched in again and made the journey back.
Is there any way to ‘cancel’ an entry to avoid having to make such a journey?