E-Cigarette 12V DC 1.5A Power Adapter Not Firing 1.8Ω Atomizer—Possible Causes?

So I am an untrained hobbyist looking for a little advice. I wired up an e cigarette to a 12vdc 750mA power adapter with a single coil atomizer measuring 1.8 ohms. It was as basic a circuit as possible with a single button/switch wired into the positive lead, and the negative grounded straight to the 510 connector, the button/switch I used was repurchased from a computer mouse. It worked great for the better part of a day before it stopped. I thought that I burnt out the power supply so I found another 12vdc rated at 1.5amps. The device still does not work. It reads 12.4 volts at the connector but I am not getting any real amperage to the atomizer. I tried a new button that I picked up from radioshack thinking maybe it was the first button that was broken but that did not fix the problem. Any ideas why it would stop working? I feel that I have replaced nearly all the components except the actual 510 connector, and can not get this dang thing to work again. Thank you for your help

When you say "any real amperage" I assume you measured the current going into the atomizer coil? - how much current was going through it?

May the coil itself got damaged / did you check the resistance of the coil after it stopped working?

Thank you for the reply. I did check the resistance and my multimeter gave me 0.5ohms. I feel that I may be causing the error there. I did test the atomizer/coil on a friend's vaporizer and it worked fine. When I tested the 510 connecter for current it read 0.2-0.4 amps.