Continuous error logs on the Netscaler dashboard as below
"8699 77 PPE-0 DBSMonServiceBinding_login.microsoftonline.com:443_(tcp-default)(vpndbssvc_1339998057): DOWN; Last response: Failure - Time out during TCP connection establishment stage"
This bug has been fixed in version 13.1-57.26 and verion 14.1-43.50
Referance Bug ID NSHELP-38736 to refer in Release notes
This is a known behavior when SAML logout URL is configured on NetScaler via SAML Action.