RecoverPoint is faking the size of a LUN

I get the following WARNING: RecoverPoint is faking the size of a LUN in the replication set (part of it is not being used for replication).

This is after I expanded a LUN and its replication partner from 1500 to 2000 GB.  Both LUNs are 2000, but vSphere can only see 1500 GB.

When I go to Manage Protection and select the CG in the left pane, the Replication Sets tab and select the set, all the controls are grayed out. Status is green.

What should I do next?

Help -> About says "Unisphere for RecoverPoint Version 4.0.SP2.P1(m.29)" -- is that the version of my RecoverPoint?

Sorry to be so ignorant -- I inherited the job of managing this in a small biz where the previous guy died unexpectedly.

Grateful for any guidance.

-Mark