Good news.
You still play a straight and polite bat, the process isn't concluded yet.
Thank you for your email dated **** acknowledging your error in this matter.
As you know, I had to pay your agents £****(the precise amount) in order to prevent my goods being seized. In order to bring financial closure to this part of the matter, this amount should be remitted by the council promptly and I do not think it unreasonable to ask for this to be paid within the next 7 working days from the date of this request. My bank details are as follows:
A/c name:
A/c number:
Sort code:
Thank you.
*- 7 working days is the same period given in a Notice of Enforcement(

. This gives a clear and in my experience achievable timeframe, but only if this is specifically 'owned' within the council and not subjected to the normal payment process.
Don't push your luck by trying to get your £70 refunded because you'd be mixing compensation with a refund. Keep them separate....which isn't to say we won't be returning to the matter.
No complaints, no recriminations......yet.