Thank you

Hello guys, I need some information and advice about the charge notice I have received. It is issued by the Department for Transport on 18 October 2022, and the contravention date is 27 Sept. First time in my life I crossed Dartford tunnel and did not know about any charges for crossing the Tunnel until I received the charge notice. I may have missed the warning signs about the charges for crossing the Tunnel. My query is "is there a legal time period in which the authority is supposed to produce the charge notice to serve the vehicle owner? such as within 2 weeks or more of the contravention date or there is no time limit to serve the notice. I would ask anyone provide me with above query ASAP as I have only 3 days left to pay discounted charge. Thank you