It sounds like you are having a connection issue. You could check your 510 pin on the mod (it's where the tank screws in) and make sure it's not stuck or pressed down. The other thing that could be happening is that your tank's pin is too short for the mod to read. You can unscrew the tank, turn it upside down, and you'll see what looks like a screw, get a screwdriver and untwist the screw head a little bit, which will make the pin longer, and may help your atomizer register. You want to make sure your coil is screwed in tightly, but not ridiculously so... a hair tighter than finger tight is what I usually do, but I'm still only using my fingers, LOL.
All of the above may work, or none of it might. With that said, if you try these remedies and are unsuccessful, I'd suggest taking it to a brick and mortar if you have one near you, to see if they can help you out. If it's an online purchase, you may need to warranty the gear.
Normally, I'd say try the tank on a different mod, but I guess you can't, yet.
MOST OF ALL, don't let this discourage you from starting vaping, sometimes starting up can be a bit difficult.... It's also good to have a backup vape, if you really want to quit (this could be something less expensive) so if something happens to one setup, you aren't left stranded.....
Best of luck and welcome to ECF, good luck in your quest to start vaping!
Anna