Potty trainnig going backwards

Our daughter is nearly 2.5 yrs old. We started potty training over the long Easter break. After a week she was doing quite well and had 4 dry days in a row. But she doesn't at all recognise when she needs to go, it's just if we got her to sit on the potty she would go. She has quite quickly got fed up of us asking if she needs the potty (we ask every couple of hours) and decided to hold onto her wee for 7.5 hours last weekend even when agreeing to sit on the potty. She eventually wet herself (and it was a lot as you can imagine). For the last week we've suggested the potty but most of the time she says no so has had accidents. Any tips on getting her to at least agree to using the potty again. Stickers have been hit and miss.