So, the mod "recognizes" the coil when first inserted, but won't "fire" it? It gives the atomizer short "message" only when you try to fire it? I just want to be sure what your issue is.
I'd say the coils would be the place to start but if it continues, you may be having some issue/problem with the 510 connection (it may need to be cleaned, both the mod pin, and the 510 connection on the mod. It's possible some gunk or eliquid got in there, causing that to happen. I'd probably start (personally) by disassembling and cleaning the tank and a new coil (from a different blister pack if you have one) and if that doesn't work, take a look at your connections.
If that doesn't work, it could still be an electrical fault in the mod, that is intermittent or somehow interfering with firing the coil. So if you try the above solutions I might take it to a vape shop that's decent near you (if you have one) to see if you can get some "in person" support. Worst case, you can warranty your setup if it's still under the warranty period. I hope it's something simple you can fix, but if not, the vape shop can probably put a different tank on there (and try your tank on another mod (if you don't have either to try) and help you isolate which part of your equipment is not working, which may help you out with warrantying if necessary. Etc.
Best of luck,
Anna