Help! Dog in my care bit postman!

[Flawedperfection]

In a nutshell..
I am dog sitting atm and on our morning walk, when a postman walked past I said hello and asked him a question, only for the dog (small terrier), in my care to lash out and nip him on the leg. This happened incredibly quickly, the postman didn’t provoke the dog in any way and it was over just like that. The postie (a young guy) was understandably furious and swearing away and I just gormlessly kept apologizing as was pretty shocked.
I later saw the postie again with another postie colleague and I apologized again and said I would get the owner to call the Royal Mail (as didn’t want to bite and run so to speak and thought this was what you did in this scenario?). The nipped postie ignored me (don’t blame him) but the colleague told me not to worry and that “these things happen”.
Have googled but can’t see legally what I can/need to do now as the dog was on a short lead in a public place. Anyone know of next steps?
And also, even if I don’t tell owner or owner does nothing, this is one of their local walks and they would be seen if ‘trying to hide’ from authorities etc.
Maybe I’m overthinking this as I’m an anxious, law abiding type!

As it wasn't at your house and they didn't take your details I doubt that there would be repercussions.
I would tell the dogs owner though. If a postie gets bitten in their rounds they can refuse to deliver to that house and you have to collect your post yourself. Make sure nipper is closely supervised now at all times.

I'm pretty sure if the dog is insured you (well the owner) needs to notify the insurer that there has been an incident.

My dog bit a postman (postie walked into my dog so he reacted) Similar situation to yours in that dog was on a lead but we walked round a blind corner and all crashed in to one another. I gave all my details to the postie and we had a follow up visit from his manager a few days later to check the dog didn't have access to where the post is delivered despite it not happening at my house. Manager was fine and said these things happen. He was satisfied that the dog can't get near any posties at home and I changed my walking times so we now avoid posties completely just in case.