Use it only within both the bag maker's and the oven's instructions, including clearance and temperature limits. A bag suitable for one cooking method may be unsuitable under a grill.
What the observation means
The bag can expand during cooking, so its empty size is not the whole clearance question. Ties, packaging and the supporting tray must also be heat appropriate. A material described as food-safe is not automatically oven-safe.
A useful next step
Check the approved mode and arrange the bag on suitable support before heating. If it melts, smokes or contacts hot parts unexpectedly, stop cooking and allow safe cooling. Do not pull melted material from a hot element or run a cleaning cycle to burn it away.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.