Thats a good looking bud you got there.. Im no expert but I though you cure it longer than 4-7 days, more like 2-3 weeks... but probably not your problem.. Are you letting some air get into the jar...Dont you sometimes open the lid to let it air out.. there must still be some moisture in there... I am just guessing.. I am sure someome will be able to help you out... What strain is that? sorry I couldnt be much help.. I would like to see what the solution is