WCF application not working via Access tunnel

I have an Access controlled application configured that I’ve confirmed is accessible in a web browser when authenticated via WARP (just the default IIS landing page). However, when I try to connect a .Net WCF client application to a SOAP endpoint, it cannot connect. From the error logs, it appears to be getting a login page response back from Cloudflare. The application also uses Windows authentication. This is a POC test to try to move away from VPN. Any help would be greatly appreciated!