After using the qPCR days before for a multiplex reaction, I created another run template for a singleplex reaction and set the thermal profile. As I started the reaction, an error message from SDS v1.4 popped up on which was written "Failed to load the tray. Make sure the tray is in. The run cannot be performed." I placed the plate properly and started again but the same message kept showing up. What do i do?