I just received my Mini 2.1 yesterday, loaded up a carto, used it last night and this morning. When to hit it again in the car, on the way into work, and nothing. Is it possible the carto failed?
Happened to me once and the reason was very silly (after I figured it out). In the middle of using a carto I put it on some other mod to compare. The other mod has pushed the positive pin a bit deeper into the carto, after which it wouldn't make contact in a Reo. Check that, it may be that simple.