Accidentally dropped Litter

Hi there, looking for some advice on a fine l've received through the post. This is also made worse by the fact I have been in another country for almost two weeks and I haven't seen the letter until today. There is no proof that I have littered it's just that some enforcement agent has "seen" me litter. Any help really is much appreciated.

Thankyou

This is a criminal fixed penalty issued under the Environmental Protection Act. Contesting it in court is probably not wise but if you post the letter we can take a look.

As far as I understand for criminal charges they are not required to share evidence till the matter reaches court.

Even if I have proof that I put the “litter” In the bin? Tried to upload a photo but it says the file size is too big

Here is the photo link

https://imgur.com/a/gq54ndx

The whole situation was very weird, I literally dropped my cigarette butt out of my window not paying attention and before I could get out of my car to pick it up two “enforcement officers” knocked on my window demanding payment. I didn’t walk away from
The rubbish or anything of the sort. I then picked it up and put it in a bin maybe 60 meters away “closest one”. These officers refused to show me any ID and wouldn’t tell me who they worked for. I then whilst on the phone to family to ask for advice what to do they walked away. As I was in the queue to pay for my parking I got talking to a lady who asked me what was going on, this lady happened to be a judge for the magistrates court of south Basildon and Essex. She said to me “I deal with these cases all the time, these officers are on commission, if I was you wouldn’t pay the fine and I would drive away” now I have receipt of the ladies name and her title at the magistrate’s court. **Sorry for the long message**