Win SCP upload to R2 bucket

I’ve connected to my bucket, and can pull files off of it in Win SCP. However when I try to upload a file I get the following error.

Authentication failed.
The request signature we calculated does not match the signature you provided. Check your secret access key and signing method.

I’m not clear what is causing this issue. Not much documentation out there to support this.

I need to be able to load files greater than 300mb. But at the moment I cant even upload a small file.

Any tips or suggestions?