Welcome to Vapor Talk! I'll just add that if the cart pulls out that easily, you may want to try another cart. Some do fit more snugly than others. Still, as Jeff said, condensation will build up around that area. Keep a paper towel or tissue handy and wipe that part off ever time you top it off. You may also want to check out direct dripping.
When I first started vaping, VT Tobacco was all I vaped and was the only thing that tasted... "right" to me. It took a while before anything else was good. Also, your taste buds will change as you quit smoking, so put away what you don't like and give it another try down the road.
What is direct dripping