My size is shown as 34 A but it’s available , can I buy 34B instead will it fit properly
You may try the sister size 32B (Sister Size down) or 36AA (Siser Size up). https://www.shyaway.com/bra-online/32b-bra/. To know more about sister sizing, read our blog https://blog.shyaway.com/know-your-sister-size/