It can be hard for me to guess your intention. On one hand you're saying that both equally a and b are community (no leading underscore inside their names) so I should theoretically be permitted to obtain/mutate (get/set) both of those. But Then you definately specify an specific mutator just https://smartworldeveloper.in/smart-world-69-gurgaon-redefining-urban-luxury-living-in-sector-69/