Do not change the default NCP settings on the PCS unless recommended by Pulse Secure. If you do not observe any improvement to your issue after making changes to NCP, please be sure to restore your NCP settings back to defaults in order to avoid any additional issues.
In the Admin Console under System > Configuration > NCP, please ensure that NCP settings are set as follows:
NCP Auto-Select: Auto-select Disabled
Read Connection Timeout: 90 seconds
Idle Connection Timeout: 120 minutes (If you have increased your ESP Key lifetime to something 120 minutes or greater, you will likewise need to increase your NCP Idle ConnectionTimeout to a greater value)