If you are referring to a "gap" between the edge of your tooth and the aligner, than it is an indicator that the tooth is not "tracking". This can occur for a number of reasons. not enough room for the tooth - some additional space may be needed for the desired movementno...
It seems that Invisalign is not working out for you with your current dentist. I would recommend completing your current Invisalign treatment, then requesting a refinement. If after completing the refinement, you still have bite issues, your dentist should offer to adjust your bite....
I would recommend you go back to #1. Even though #4 fits now, it will get harder to continue to later aligners and your teeth will not track the way they are suppose to.Good luck!