Configuring Juniper EX4300 Virtual Chassis

Hello, we've 2x Juniper EX4300 Switches and we're trying to set up virtual chassis but after connecting them with each other over the 40GE Port on the backside, the second switch took over the entire configuration of the first switch and now the VC doesn't work at all. We've tried to revert the changes but it simple doesn't work as it should. We need someone to troubleshoot this issue and find a solution to either make the VC work or at least help to set up the second switch back in trunk mode in order to use it. Regards, BlazingFast