We’ve just potty trained DS who is 2.5, and as PP said, it’s something you need to be committed to rather than casual encouragement every now and then. We have friends who have a child who is almost 3, and they’ve been potty training for 6 months - but again, not taken it seriously and instead casually suggest it every now and then. It was their experience that made us decide to do it properly when we started, and we did it over the bank holiday weekend and took an extra day off, so we that we spent 4 days at home not going anywhere so that we can focus on it.
We also geared him up for it in the run up. To be fair it massively helped that nursery said he is curious about children using the toilet so he was keen to do what some of the the other children do, but we also read books, got him excited that he’ll not wear any nappies anymore, and that he’ll pee like mummy on the toilet (and then I would list all the other grown ups in his life and tell him they also pee on the toilet).
We’re not completely there yet, so I’m not going to act like we’ve cracked it, but we’ve made really good progress.
Another thing I read a lot, and which we did with DS, is keep him naked from the waist down. On day 1 we kept him completely naked but after that, he wore a top which we rolled up so that it didn’t sit below his waist. The theory is when they actually see themselves peeing and having accidents, they are more likely to understand what peeing is, what it feels like, and why they need to sit on the potty.
Oh, and one more thing - don’t ask them if they need to pee or sit on the potty, tell them it’s time. Asking always results in a “no”.
It’s hard work, but she will get there! Good luck!