You need to disable Detect Protocol in the Visual Policy Manager (VPM) for Edge SWG (ProxySG) or Cloud SWG (formerly known as WSS) in Universal Policy Enforcement (UPE) Mode.
You may need to complete this action if a Symantec Support has advised you to do so.
Also see: Why doesn't a detect_protocol(no) rule work for some sites or applications when applied in the VPM?