Most of themes usually come with a microdata markup which is implemented based on the vocabulary.org language…you might need to rewrite some JSON LD scripts which will be implemented in your functions.php file or you can as well use schema pro plugin for your structured data markup.
Specifically for breadcrumb, you may need to disable the default one that comes with your theme and implement a new breadcrumb structure using breadcrumb navxt plugin which has the correct schema markup based on the schema.org system.
This might require you to do some CSS stylings just to make the breadcrumb appear the way you want.
In all, the solution will depend on the wordpress theme you are using. You might also need a developer to help you write the schema or install the breadcrumb using Breadcrumb navxt which I have done previously. But if you are familiar with codes, you will be able to do this yourself.