Your question is a bit confusing in the way it's worded. Is the coil a 0.15 ohm coil, or a 0.22 ohm coil? Assuming it's a 0.15 ohm coil that's reading as a 0.22 ohm coil, the remaining resistance difference is likely a combination of the resistance in your atomizer and the internal resistance of the mod. I'd recommend letting the coil cool down to room temperature, then checking the resistance in the atomizer analyzer to see what resistance the coil is reading as. You shouldn't have any need to lock ohms on a DNA 200 device unless your resistance value is fluctuating too much due to the atomizer not having a good connection. If it works fine without the resistance locked, I'd say to simply leave it unlocked.