Use the model's accessory diagram and approved placement. A griddle must not simply be laid across whichever burners appear to fit beneath it.
What the observation means
Its shape, supports and heat distribution are designed around particular locations. Covering controls or vents, or bridging an unsuitable pair, can create problems. The permissible heating method may also differ from ordinary pan use.
A useful next step
Follow the griddle's preheat and cleaning instructions without improvising a hotter arrangement. If it rocks or obstructs other parts, leave it unused until compatibility is established. Do not bend pan supports or substitute an unrelated plate to recreate a missing accessory.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.