Problem updating from plesk 8.1.1

[VPRI]

Hello everyone,

First when we try to update from version 8.1.1 to 8.2.0 we get this in our logfile:

Error Message:
Service not enabled for system profile: "vpri-plesk"
Error Class Code: 31
Error Class Info:
This system does not have a valid entitlement for Red Hat Network.
Please visit https://rhn.redhat.com/rhn/systems/SystemEntitlements.do
or login at https://rhn.redhat.com, and from the "Your RHN" tab,
select "Subscription Management" to enable RHN service for this system.
Explanation:
An error has occurred while processing your request. If this problem
persists please enter a bug report at bugzilla.redhat.com.
If you choose to submit the bug report, please be sure to include
details of what you were trying to do when this error occurred and
details on how to reproduce this problem.

ERROR: The up2date utility failed to install the required packages.
Attention! Your software might be inoperable.
Please, contact product technical support.

And this shows up on the next screen:

Error: Select the components to be installed

Then if we try to update again we get this:

ERROR: PleskFatalException
Undefined release.

0: /usr/local/psa/admin/plib/common_func.php3:151
psaerror(string 'Undefined release.')
1: /usr/local/psa/admin/htdocs/server/autoinstaller_install.php:16

Could anyone help us out? Thanks!