Certificate authentication with Password in IKEv2 (IPSec Dialup)

Hi guys, i´m trying to build a VPN with a certificate authentification(warning im a newbie on Fortigate). This is alredy established and works, but the connecting process the user dosent have to type a password or username in. So how can i get a authentification requierement for certificate user. For example: User have certificate -> connect -> Type Password & Username in (this dosent come???) -> connection established The connection is via Linux network-manager-strongswan Fortigate Version is 5.6.3 (Fortigate100d) The next Question is i have a limit of 10 parallel VPN Users on the Fortigate, how can i increase it? Thanks for your help. :) PS: Sry for the bad english.