I have the Smok Prince RBA and it's their usual hit & miss quality, the deck short fuses and the ohm's jump around.
It's a similar workaround to other Smok RBA, in this case the base is too long so if you assemble the proper way you get problems, if you screw the base into your mod first then nip the RBA finger tight it usually works, this happens on every build I have done on it, I could be just unlucky and got a duff one.
It's the same when trying to build on a Coilmaster deck, if you screw the base and RBA first then it won't screw all the way down on the deck.
You can see the problem as it pushes the 510 pin too far.
I am going to grind about 0.5mm from the base and see if that sorts it.
I've bought 5 assorted Smok RBA's and only 2 worked properly (1 was already cross threaded, 2 had the silicon seal fitted wrong and the other I had to hammer the centre pin)
I hope you have more luck.
On the plus side, when you get your build right the tank is superb! despite it's flaws it's my best tank for flavour, the massive air vents and juice holes just work.
(the stock coils are overpriced and crap quality, fitted one lasted all of 3 tank fulls at 65 watts before dry hitting, and the other was way too high power for my taste.
I currently have Alien 5 wrap coils in mine coming out around 0.24 Ohm's but I prefer the original fused claptons.