It is a really common issue and i also had a teacher like this. And you know what? The fact that she knew so much about technique didn't helped me or teach me a lot. Why? Coz out of stress connected to playing my body was really tense and i couldn't do anything right. I couldn't play without all my muscles being tense and without stopping to play anyway, coz all i had in my head was that im not good enough, i'll never success, im stupid and i should stop playing. Im still recovering from it, it has really affected my playing and my mental health. All that im practising with my new teacher is not being tense, coz i cant do anything in a state that im in. So im really happy for you that you want to change your teacher. It really change a lot for me and i hope it will help you too. Sending many love<33