You won’t be allowed to get a new OEC to replace your lost copy. If you got your latest OEC through a walk-in application, go to the POLO in your host country and submit a notarized Affidavit of Loss. Request also for a certificate with details on your last issued OEC.  To prevent it from happening again, use the BM Online system to get an OEC next time. This way, you have an online copy of your OEC and print it when you lose your copy.