Oh no, sorry to hear that - don't worry, we'll get you back up and running in no time.
Please tell one of our admissions team and they will show you where to get a replacement card. If you have ID with you then it may speed up the process, also there is a £10 re-issue fee per pass.
If it's a Merlin Annual Pass that you bought from somewhere other than Chessington, then you'll need to return to the attraction you got it from to have it re-issued. Sorry about that, but it's out of our control unfortunately.
We hope this answers your question.