Was it showing low charge on the overhead display/control panel? What charge does it show?
I have read on other posts that the battery level indication is not the most reliable.
If it is an Ocean as per your membership profile, then it actually has two leisure batteries. One under the passenger seat and one in the bottom of the rear cupboard unit on the nearside.
It could just be that both are low on charge due to them not being fully charged when initially installed at the factory, the van standing around for a while at the dealership and/or the dealership has partially discharged the batteries whilst testing out the various pieces of electrical habitation equipment. Or perhaps they left the fridge switched on after doing some initial checks on it.
There is an option in the overhead display/control to select maximum charge for the batteries. This can be selected once the engine is running and it resets once the engine is stopped.
As a first step, if you are driving the Cali around over the next few days, I would select this option each time you go for a drive and see if the battery indicator on the overhead display/control panel shows an improvement.