The ideal temperature for drying cannabis should be between 60 and 70°F, with a relative humidity for drying cannabis sitting between 45% and 55%, so if you're at 68 °F now you're still in range and it's not too high, just make sure to not go over 70°F because If the temperature is too high during the drying process, it can cause the buds to dry too quickly, leading to a harsh smoke and undesirable taste.