Check your license boot:
show run | include boot
And if you don't see it there already, add it like this:
license boot level appxk9

*edit: in your case, you made need license boot level securityk9

Check your license boot:
show run | include boot
And if you don't see it there already, add it like this:
license boot level appxk9

*edit: in your case, you need license boot level securityk9
After adding the boot level and reloading, you should be able to accept the EULA and gain access to ISAKMP/IKE commands.

Check your license boot:
show run | include boot
And if you don't see it there already, add it like this:
license boot level appxk9

Check your license boot:
show run | include boot
And if you don't see it there already, add it like this:
license boot level appxk9

*edit: in your case, you made need license boot level securityk9