Credit score help

P23

Im after some help with my credit file please!

5 years ago I moved back to my parents home but left some debt at the old address where my ex still lives. I defaulted on a card at that old address almost 2 years ago and I have another credit card and a store card at that address along with a shared mortgage which are all up to date with no missed payments. I do have another settled defaulted account which will drop off my file in 6 months.
At my current address I have an overdraft and 2 cards which are up to date, I have 2 missed payments from 2-3 years ago but that is it.

I recently got my credit file from Experian a few months ago and it put me at 804 fair, I've logged on since and it has updated with all my old debt and changed me to Very Bad with a score of 0! I understand that a default is really bad but as I have been up to date with all other payments I'm surprised I have went so low to 0. Could the fact that I have different debts at different addresses be a factor on this? Or is this drop in scores mostly from that default? Can anyone advise on what I can do to start building it up again?
The default is due to be settled in 1year with the payment plan I am on, though I hope it will be 6-7 months with overpayments. I'm working on that 1st before paying off other debts so it is settled, is this the correct thing to do, settling the default before my other debts? After that I understand it will take 6 years to be removed from my file, I've accepted that this is my own fault. I've been reluctant to change the addresses on my accounts due To I didn't want it to have any impact on my parents. Although I'm not financially associated to them, am I right in thinking that my credit file at my current address would not affect them?
Any help on the above would be appreciated!

Hazzinho

Credit files are on an individual not an address, you only impact others where you are financially associated through joint accounts. Ignore the scores they mean nothing, only you see them. Get the £2 reports as and when you want to view them for Experian and Equifax and get the free one through Noddle (Callcredit). Just ensure data is accurate, you keep up your repayments and you are on the electoral roll.

P23

Thank you - I'm so pleased my parents wont be affected! I don't have an association with them thankfully!
I had signed up for the 14.99 Experian report but think I'll cancel that now and get the other 2 for £2, seems like a waste of 15pm at this point.