Not necessarily. Some seals have an intentional arrangement or opening, so compare the shape with the exact model's documentation before assuming a piece is missing.
What the observation means
A designed gap is different from a tear, displaced section or brittle material. Sealing every opening with adhesive can interfere with the intended ventilation and make later servicing harder. An unrelated replacement seal may also have a different layout.
A useful next step
Photograph the visible condition while cool and identify the model for advice. Do not stretch, cut or glue the seal to make it look continuous. If the door no longer closes normally or heat damages nearby surfaces, stop using the oven pending assessment.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.