Help! Debt collection letter Ikano Bank

[Matt123]

Hi,
Looking for help please.
In August 2015 myself and my wife took out an interest free finance agreement through Ikano Bank. The agreement was for 30 equal instalments commencing on 13th October 2015 and paid by direct debit.
It was at this time that we were moving house and we wrote to all our creditors (including Ikano) to inform them of this.
We didn't hear anything further from Ikano, but made all payments on time as required and for the correct amount so assumed everything to be fine. This I think is important so I will repeat - made all payments on time and for the correct amount.
Then in March 2018 having made the 30th and final payment we cancelled the direct debit as all paid up. Great - right? We then received a letter saying our direct debit had been cancelled, but we knew this and have received end of DD notices before. We heard nothing more until August 2018 when we received a letter from a collection agency for £144. We contacted the agency to query this and they were fair and reasonable, placing the account on hold while waiting for Ikano to respond. 3 weeks went by and no update. Contacted them again - still with Ikano.
So, because we were worried we contacted Ikano direct (nightmare getting through to anyone!). When we finally got through and gave our address they said that the address they had was our old address. They then confirmed all payments had been made against the original credit agreement BUT there were outstanding Admin charges on the account because an annual statement issued in September 2017 had been returned to sender. I said that if that was correct how did they write to us at our current address to tell me the DD had been cancelled? Said they didn't know but I must pay!
Having checked T's & C's it does say they can charge a reasonable fee if they have to initiate trace proceedings.
Anyway, point being we didn't default on the agreement ever and had they needed to make such a charge to trace us, then surely they should have written to us at the correct address to tell us this and give us chance to remedy before forwarding to collection agent? They did have my correct telephone number and email address.
They have also recorded a default record on our credit report.
I am in the process of writing to them and will take it as far as I need to to rectify this injustice.
Any help greatly appreciated?

[R0b]

Hello Matt123,

You need to split out your text as it is clumped together and can be difficult to read.

I think it is important to know in what context, they can charge a reasonable fee. Usually tracing agents are used to locate a debtor when there is an outstanding balance on the account and particularly where there has been no contact from the debtor. But I would have to question why they instructed tracing agents (if indeed they did that) when presumably, they would have had a contact number and email address on the account - they could have simply called to verify the latest address!?

It would be helpful if you could upload the terms and conditions so we can actually read what it says about reasonable charges.