Car Accident

Hello folks,
Yesterday a man hit me by can when I was cycling closer to Malahide Castle.
At the begin he was polite, gave me his number and name <snip> and asked me if I needed support. I answered that I was fine, not 100% but I was ok.
However my bike had some problems.
I sent him a message saying that I was about to put my bike in a repair shop and asked him if he had a preferable shop for that.
He answer that it was fine. I sent some pictures of my bike to him and informed that I've no idea about the price, because they'll check all conditions before tell me the price of the fix.
But today I tried to talk to this guy but he blocked me on Whatsapp and message.
What am I supposed to do in this case?

Yes as Brian says, your first port of call is reporting the incident to the Gardaí and if you do not have the number plate of the car, the Gardaí should be in a position to track him through his mobile phone no.

Thank all.
I'm going to do that right now.
But I remembered him that internet is public.
I got all his information, address, drive license, vehicle plate, id, facebook, etc and sent him a message with all these information about him with an online account and he came politely talk to me.
But for sure I'm going to Garda right now.
Thanks

Nearly the exact same happened to me, I tried for a while to get payment as I had already forked out eventually I dropped it but I regret not going to the Gardai at the time.