Defaults years after moving

Confusedin2020

Good Afternoon All,
First time poster, i hope someone can help!
I have just been turned down for a mortgage due to having 2 defaults on my credit score. 
I didnt know they existed until around a week ago after looking at my credit score following the rejection.
The two debts are from Northumbrian Water & NPower. They are from an address i moved out of in 2013. 
Although i am going to pay them in full. I am wondering if they are allowed to register the default years after i moved out?
Northumbrian water Default Date: 13 Feb 2017 - 4 years after i moved
NPower: 14 Dec 2017 - Same again, 4 years after i moved
I always thought that defaults would have to be registered 6 months after defaulting. Its my fault for getting them, the amounts are pretty small and ive obviously not paid the final bills. But it seems unfair that they have registered the default so long after they actually happened.
Can anyone help?

[Deleted User]

You could ask them to backdate the dates to a more appropriate time.

Presumably these were from two separate addresses, as you say each was 4 years after you moved, but the defaults are almost a year apart. You should check all three files to see if there are other utilities hanging about from either address.

Confusedin2020

Sorry i wasnt clear, they were from the same address, i moved from the address in January 2013.