Many factors to consider, yes chain or heavy vaping will heat up a coil and tank and lessen coil life, for sure. Juices: Sweet, dark, NETs or WTA as well as super high VG will also burn coils. I have found having several setups in the morning when I want to chain vape is helpful. Make sure to prime your coils well, let them sit a while, then slowlllly raise wattage while taking long slow puffs, until you get your vape where you like it. Don't let your tank run lower than 1/3 or 1/4 before refilling, the less juice, the more the watts will heat it up. Don't drain your tank.
Some folks poke holes in Smok coils to assist in wicking. You can use a needle or syringe and just poke and fluff the cotton in a few spots. That might help you.
Honestly though, depending on how much you are vaping and wattage and airflow, it's not unheard of for coils to not last a long time (drop in coils specifically) until you find the right type of e-liquids without too much gunking factors. One thing I might try would be a few drops of water in your tank with your e-liquid, it will thin it slightly, and possibly reduce temperatures in your tank.
Best of luck,
Anna