I accidentally scraped up against a parked car while attempting to park. There were only a few very minor scratches on the car and my car was left with a few scuff marks. I waited for 30 mins and the driver didn't turn up and I also knocked on a few doors in the street but couldn't find the owner. So I left a note explaining it was a complete accident and left my name and phone number. I put the note underneath the windscreen wiper. It's now nearly 10pm and this happened at 1pm this afternoon and I have had no call or text from the owner of the car. Are there any other actions I need to take? I also took a photo of the damage but stupidly, I didn't note down the car reg number. Do I need to inform my insurance company?

Thank you