Buying house garage has no ccc

We have made offer on a house which has been accepted banks are dealing with it now

The garage at the property has a dwelling attached to it has no water but has power

When this was built in 1997 building consent was granted and was completed but when they went to apply for ccc it was not given as the time had expired for it to have obtained ccc I have a letter from the council saying that this is what happened but they have said it’s safe and sanitary and was built to code I have asked insurance if this is a issue for insurance they said no it’s not I have sent all this information off to the bank

will this be ok it’s goes all the way back to 1997