What collision ?

Scam?
Ignore?

It's on headed paper and gives my details and hers. Name, address, Reg, insurance details.

Contact your local police station or if possible go in to the station with your driving licence and documentation.

Similar happened to me several years ago, turned out our car reg was being used for a similar model/make of car.

Ignore! I also think that this is a scam.

On second thoughs! Maybe as GrannyGravvy says!
Take it to a Police Station.

Sorry just to clarify, are you saying the letter from the police is a scam or her claim ?
Obviously she is scamming.

I agree, go to your police station. It was the police who contacted me for something similar which happened to GrannyGavy but it had been the previous week so it was easier to prove where I was and it was not in SE London.

Have you lent your car to someone else? That happened to us once - neighbour borrowed our car and had a small bump and didn't tell us. The Police came round to us, at the back door.
I'll never forget it because we were all sitting at the kitchen table eating dinner and when they knocked husband yelled 'Go Away' he thought it was the neighbour. Then through the window I saw 2 policemen leaving and ran after them.
Got it sorted in the end.

Grannygravy the details of my car are correct and I was driving on the roundabout at the time she claims it happened.

No Fennel I was driving at the time and place mentioned.

In that case she is lying to the police which in itself is an offence. I would still go into the police station, with documentation, unless you or she has a dash cam, she must have proof, as the police do not just take people's word that there has been an accident, and if there is no injury to the persons involved it is very unusual for the police to get involved, it is down to the insurance companies to hash it out.

I had this a while back. Had rows with my insurance company who insisted it must be me as it was my reg. number although the make of car was never confirmed. It went on for months until eventually someone realised that the reg. number had been written down incorrectly and was a case of mistaken identity. No apologies

It was all very stressful as everyone assumed I was lying.

So you actually were driving on this Roundabout, with your Husband in the passenger seat at the time stated by this person.
It seems to me that she has given the Police your Registration Plate Number and they have traced you through it.
The Police will intervene if someone informs them of a "hit and run".
You definately need to take the letter and your documentation into a Police Station. Tell them that you definately did not hit any car, at all. They will log that you are the person who she is accusing of damaging her car and from then on I think that you have to deal with her and her Insurance.
What could have happened, is that a car, DID clip her car on the roundabout and by the time she got her wits together to look at the Registration on the car, the other car had "took off" and yours was behind it.
So she's mistakenly, blamed you.
Or she's an absolute Scammer and just taken your number and will ask you for X amount so you don't have to claim through your Insurance.
Don't hand any money over before you see the scrape yourself.
It's not going to be easy, although if your Insurance gets involved, they will check that any paint scrape, matches the colour of your car.
Unfortunately, if you do have to contact your Insurance, your premiums will go up.

Hi GrannyBags, I've only just read this thread and whilst I can't really give any opinion on the main subject other than agreeing it's probably a scam, I was intrigued by you problem with your insurance company. My sister had an ongoing issue with hers earlier this year and the company were clearly at fault. She complained and pushed for compensation, she eventually was reimbursed for all her phone calls and a sum on top for all the hassle. Worth a try least, after all, they do get plenty of cash out of us!

Could be a scam but would definitely clarify with the Police.
This happened to DD in Australia. The police turned up on Christmas day (nothing better to do?) accusing her of a hit & run in a place she'd never visited. Her Reg No had been used, possibly taken from a garage where the car had been recently. Luckily she was able to prove, thanks to automatic photographic billing for Sydney Harbour Bridge, that she'd been on her way to the airport at that exact time, 40 miles away, to fetch me! If she hadn't I shudder to think what the outcome might have been. There are some nasty people about wherever you live!

I repeat, there was no collision.

An update. I had a letter from the police yesterday stating no further action will be taken.

Hi H1954. I did eventually get some money back which they said was "a gesture of good will" That phrase annoyed me too!