Other
Common issue
Odor
High-temp heat will burn the oil which absorbed into the stone and cause smoke and odors. The odor and smoke will not disappear until the oil is burned off.
Stains
It's normal for the stone to accumulate stains, this is the record of your baking life. Running the self-cleaning cycle of oven or burn the stone evenly on the grill can help cleaning the stains.
The food is soggy and sticking to the stone
The stone was not fully preheated. Please preheat according to point 2 of "how to use". The stone only work after being properly preheated.