400 error would be a general error on Stripes side. Maybe try postman or curl on your own machine to make it 100% work then try it on bubble? Using bubble directly without testing could work but it adds additional complexity to troubleshoot.
Postman is great for API’s. If you want to just get this done, consider using curl directly on your machine…if you are using linux or mac, it’s already in your terminal. If you are using windows you can quickly install it then copy/paste your command above to see if it works.
This is highly specific to stripe. I’m not sure how much I can help since I haven’t used it ever. A few ideas:
I do not see you sending your token
your command is breaking up. See after you enter the command it partly executes. I do not use windows but I think the \ to break to new line doesn’t work on windows the same way.