I had this too 6 months ago.
if she is holding it then she is ready. Do not give up.
we used the oh crap method and I read that book cover to cover. My daughter went on strike due to losing control for 4-5 days. We had a great day one when it was fun and then absolute horror story after that.
she would refuse all day then wee in the nappy at nap and bedtime.
I had to go for drives alone for my mental health as she was so so difficult. We could not tell her, it was her catalyst. We decided to say nothing. we never asked her, it just ended in meltdown.
Anither thing that broke the ice was to take her out the house. My mum who usually looks after her once a week took her on day 5 and magically she was weeing and pooing perfectly for her then refused when she came home that evening.
The following day we took her to a role play centre with a potty to hand and she did a wee there on the potty.
She cracked it after that. Day 6. It was truly some of my worst days of parenting prior to that but she did come around very suddenly.
We are 6 months in now and we still rarely ask her if she needs to go, as NO is her default answer to everything. We let her lead. She genuinely does not have accidents, ever.
stick at it. oh crap method.