After more 10 years the DWP finally got it

My partner is British, I am Swiss and when we moved into our council flat (2006) and applied for Housing Benefit we had to bring bank statements. I still have a Swiss Postal Account because it is easier for us, when we visit my mum, to shop or pay for train tickets.
I always assumed they realised that this account was in Swiss Francs.
Boy, was I wrong.
Fast forward 2015: I received an inheritance. We let them know.
I had to send them each year how much was in my account. I then noticed that they count my account in £ not CHF. So I wrote each year on the sent statement that my account was in CHF. But whoever dealt with it each time ignored it.
Fast forward 2019: We are now below the threshold and let them know. Did hear a word so we rang. I was told I had to send all the receipts of our spending I mean who keeps everything? Anyway I sent them approx 2kg of papers and again a letter explaining that my account was in CHF not £. That was in February.
We heard nothing. In March my partner dropped off his sick note at the Job Center and asked what was going on. The replay was that the case was dealt with.
Another 3 or 4 weeks later we didn't hear a word. So we rang and spent around 40 minutes waiting and 30 minutes explaining the problem. We were told someone would ring back. Didn't hear a word.
Last week my partner had an inexplicable payment from the DWP.
Rang up today, waiting 50 minutes. 5 minute on the phone, were told we have income support back and a letter is on its way.
Please, if you have a foreign partner with a foreign bank account make sure the DWP understands the currency is not £. It'll save you a lot of headaches.