Once a disposable dies that's pretty much it, toss and replace, Sadly, just like buying drop in coils there are bound to be disposables duds. I understand you wanting to use them for the super no fuss convenience and because your friends do but honestly going by your posts you are experiencing a lot of issues that you don't need to be. If you visit your local vape shop they will have small profile units much like your disposables that can be easily recharged over and over with pods that can be refilled with high mg nic e-liquids equivalent to what is in your disposables that they also can sell you. AIO or Pod systems, that come with the coil already in place in the pod. In the long run it will save you money and frustration.