As I understood, your migrations are not in sync with your database, because someone was changing the database directly.
You can regenerate your models, DB context and entity configurations from an existing database. Investigate Entity Framework Database First .Net Core
If that is the case, you can delete all the migrations (whole Migration folder), entity configurations (if you used Fluent API) and DB context.
You will not have your migrations as you had, from the initial creation of the database anymore. Models, entity configurations and DB context will be created/scaffolded from an existing database.
Useful links: here and here.