Some call me paranoid, but I don’t think one can be suspicious enough when it comes to the activities of Lambeth Council.

I guessed it might be up to another ruse when I received a more than usually threatening letter at the end of July informing me that it was undertaking a review of council tax discounts. Actually, I didn’t receive it at the end of July, because I was on holiday. Along with thousands of other people who will have been sent the letter at that time, I only read it when I returned from various summer trips.

It warned me that unless I re-registered for my single occupancy discount by 30 August, the discount would be rescinded ‘from the date that it was first issued’. Let’s think about that. The discount was first issued to me in 2001. I lost it briefly in 2002 when I took in a lodger. Then I re-registered for it in 2003 when the lodger moved out and have had it ever since.

If the discount was to be rescinded like this, I faced being billed by Lambeth Council for £300 a year for 11 years. Or to put it another way, if I had been on holiday throughout August, which was still legal the last time I checked, I would have returned in September to a completely spurious demand for £3,300. This would be doubly galling because my 25 per cent single occupier discount is one of the rare success stories in my ongoing battle against Them.

I secured it after a Labour minister informed me of its existence as we had lunch when I was a lobby correspondent. I was moaning about the depravity of Labour taxes when he suddenly said, ‘Hang on. You say your council tax is £1,200 a year. But you live alone, right? You should be registering for the discount.’

I leaned in so close I was inches from grabbing him by his lapels over the table. ‘Discount?’ I gasped. ‘What are you saying? I’ve been paying all this money all this time and I’m entitled to pay less?’

He nodded, petrified.

‘Why didn’t anyone tell me?’ I was pretty much screeching now.

‘Well, it’s just that, er, we figure that if you’re poor enough you will know what benefits you’re entitled to.’

‘But I’m entitled! I’m entitled, right?’ He nodded and squeaked.

I rushed out of the restaurant to ring the council for a form and, bar the year I had a lodger, I’ve been claiming it ever since.

I have been known to finish relationships that looked like they were going somewhere in order not to jeopardise it. The builder boyfriend, who has his own house, is rarely allowed to even stay the night because I’m so paranoid I might compromise its integrity if a second human being is ever seen near my front door in the morning.

It makes a lot of things a tiny bit more bearable. For example, when I’m trying to position my bin at a 90-degree angle to the kerb on a Wednesday night when there’s a full moon I feel slightly less like throwing myself in front of a lorry because of my 25 per cent. Aside from the symbolic victory it represents, it is also incredibly important in practical terms.

Every year, after I get the letter saying £300 has been taken off the council tax, I go to the Lambeth Council customer service centre and give them £300 back in order to get a permit that allows me to park my own car outside my own house. All things considered, therefore, if the council want my single occupancy discount back they will have to prise it out of my cold dead hands. But from the look of the letter, that was almost what they were about to do.

After filling in the form and posting it a day from the due date, I rang to make sure they knew the form was coming. ‘Welcome to the London Borough of Lambeth council tax services and housing benefits centre. If you use abusive and threatening language we will end your call and action may be taken.’ It never seems to occur to them that the best way not to have their staff threatened with abusive language is to refrain from tricking people out of £3,300, but there we are.

The man at the call centre was adamant that my reading of the letter was correct. If I hadn’t informed them I still wanted my single occupancy discount in time, I would have incurred a charge for all the money I had ever been discounted since the discount first began in 2001. ‘It’s an awareness thing,’ he said. ‘People need to understand that the council can take the discount off them.’

Message received, loud and clear.