what is "rent charge" on a freehold property?

[Ippagoggy]

We are about to remortgage and the lender needs evidence of the fact that we are up to date with our "rent charge" payments. For clarity, this is a freehold property but we do share some communal areas (garage) with 6 other houses. We pay service charges every 6 months and I sent this over to the lender to show them 0 balance but they said "This is not it : service charges are not the same as rent charges".

I called the property manager and they have no idea what I'm talking about. So I'm really in a bind here....

• What is rent charge?
• How do I show that it neither applies to me or that I am up to date with it? I certainly don't recall ever having to pay for anything other than service charges and I don't see the term 'service charge' anywhere.
• If Is there some other way around this?

I thought they'd been abolished but seem to be wrong:

https://www.gov.uk/guidance/rentcharges#who-has-to-pay-the-rentcharge

They were a thing in the late 19th Century whereby your freehold house was a wee bit cheaper in exchange for a rent charge. Even before the inflation in the seventies the annual amounts had become nugatory.

Buying the right to receive the charge was a bit popular as an investment at one time.

In the early nineties I worked for a corporate trustee managing multiple trusts with rent charges. Given the number that didn't pay - my solicitor never mentioned it when we bought - I doubt they even paid the salary of the lady we employed to collect them.