It could be that your cotton is too close to the airflow hole that feeds air to your coil causing juice to run down the hole and out the bottom of your tank try moving your wick clear of the air hole [emoji4]
DIY is so much effort!
But I think I heard that in a YouTube video for this - I think they said I shouldn't be able to see the cotton wick in the airflow hole. I'll give it a go! Thanks.