Hi and welcome.
You likely have one of two problems.
1. The coil is bad and needs to be replaced.
2. The bottom pin of the atomizer is not making contact with the positive pin in the
mod. Turn off the power to the
device and gently pry up the positive pin with a toothpick or some other small tool (preferably non-metallic). Then reattach the atomizer and see if you still get the same error.