API "level" property returning null for 87676171

[magicDGS]

With the automatic testing performed on https://github.com/magicDGS-gaming/ygoprodeck-openapi, there are some issues with some schema: looks like the level property is set to null on a specific card. Checking the response, this is the faulty card:

Is it normal to have this behavior, so the OpenAPI description takes into account the values as nullable, or if it is null should not be returned at all? Or is it a data issue on this specific card?