A PhD is a long, arduous slog. There are times you hate it and times you love it, but the one thing you need is an interest in your research topic. Without any interest in the topic, I think you're going to find it extremely difficult to complete your research. It only gets harder as you progress, so I think you need to think very seriously about whether you have made the right move. If I was you, I'd speak to your supervisor and see if you can change aspects of your PhD to align more with your own interests (assuming it's not a rigidly fixed topic and research approach).