Do not run nickel coils in wattage mode, bad juju that. Check the resistance showing on your mod and see if it is close to what the coil states. Could also be a dud coil
Could just be one of your batteries has drained below the minimum voltage the rx requires to turn on. Have you tried plugging it into a computer and installing the latest firmware again?
You're mixing it about half half with VG and VG has it's own distinct flavour. That and if it is a recent mix the flavour should be pretty muted at that mix ratio. Best is to drop the mixed juice in a bottle of warm water to thin down the vg, give it one hellofa good shake, open bottle to...