Wait - you might just have helped me to fix my Invoke-WebRequest testing 3rd party api we have to integrate with. Unexpected character encountered while parsing

Wait - you might just have helped me to fix my Invoke-WebRequest testing 3rd party api we have to integrate with. Unexpected character encountered while parsing error line 0 position 0 seems like there is a BOM I wasn't expecting to send in my request and receiver definetly was not expecting to receive it. Edit: yup, just did small cmd line client and all works. Thanks.