Trailing Slash with routes

I am using a third party service which sends post requests to my starlette instance. This service will not include trailing slashes and does not follow redirects. I can’t get starlette to properly accept the post request it always returns code 308

routes = [
    Mount('/graphql', EnforceSecretHeaderMiddleware(GraphQL(SCHEMA, debug=True))),
    Mount('/upload', routes=[
        Route('/user', accept_user_post, methods=['POST']),
        Route('/website', accept_website_post, methods=['POST'])

app = Starlette(routes=routes, debug=True)

Even my starlette test client fails if I request /graphql it only succeeds on /graphql/ even with the above router settings. What am I doing wrong? This is somewhat frustrating.