Hello - Sorry to hear you have had difficulty with the SMART CONTROL fuel can. There is a screen in the opening of the fuel can which is a flame mitigation device (FMD) for consumer protection. Their inclusion in fuel containers is about to become law. Unfortunately, there are people who misuse fuel and can end up severely injured. Our goal is the safety of our customers, so we’ve added one ahead of the pending regulations. We understand that filling the containers can take a bit longer, but this does add an extra layer of protection for consumers who don’t handle fuel responsibly. . Gas and diesel pumps are different. The FMD contains two internal ledges that the pump must rest on when filling depending on your fuel type. Diesel pumps rest on the first ledge, and gasoline pumps must be inserted to reach the second ledge. We have posted both fill and pour instructions online at www.scepter.com/starthere/ which should help. Our Customer Care Team can assist with a replacement O Ring, they can be reached at 1-855-857-3252. We hope to hear from you soon. Thank you