Cbd carts cbd crashout

Hey guys ive made 100’s of 50/50 carts mct to isolate never an issue . All of the sudden my carts and cbd base is crystallizing ive done both 15 ll to 15g and 15g to 15g. Not sure why can anyone help i meed my .5g carts to hit 250 mg even after a drop of terps its happening its only about 62 degrees in here bringing the solution up to 75 degrees c even …do i need a longer infusion time?