@OttilieKnackered It will either be Prochlorperazine or Promethazine - again, both first line.
You need to get back in contact with the GP and ask to try a second line (like Metoclopramide) or ask for advice about taking medications in combination with each other. Sometimes it can take a while to find the ones that work for you, but you don't have to live like this.
I ended up on Ondansetron, which is a third line med often used to help sickness in chemotherapy patients. GPs are (still) hesitant to prescribe because it's expensive and there may be something else that works for you first.
I ended up in hospital before I was prescribed it though. I took Prochlorperazine, Metoclopramide and Ondansetron together.
I've also heard good things about Xonvea, a relatively new med, although there have been recently supply issues.
Obviously be aware that I am not an medical expert, but I do have experience of trying lots of different anti-emetics and going back and forth the GP countless times before I found something that worked.
I know it feels hopeless right now. It's awful. I hope you manage to find something that works for you!