You attempt to place the SWG into bypass mode by disabling the service. However, the SWG does not go into bypass mode and instead blocks all traffic.
The SWG UI will indicate that the service is disabled and that the SWG is in bypass mode, however the SWG will block all traffic.
This appears to be related to a known issue in SWG 5.0.2. Currently the workaround is to temporarily re-enable the service.
Administration->Configuration->Operating Mode, check "Service Enabled", and click "Save"
This issue is resolved in SWG 5.0.3. Please upgrade the affected SWG to version 5.0.3. It is not necessary to place the SWG in bypass mode in order to perform the upgrade.
If you do require that the SWG service be disabled (bypass mode) before performing an upgrade please reboot the SWG and then disable the service following the reboot.