You will get this error when you are trying to create a budget with the same name as a recently deleted budget.
Deleting a budget from the UI is treated as soft delete in the backend of the system. The budget record will stay in the DB for a few days, but the budget status will be "inactive". Due to this, the platform doesn't allow creation of a new budget with the same name.
To free up the name, you could rename the deleted budget entry via graphql-API:
query{budgets(isActive:false){name id}}
)updateBudget
(for example, 'Budget Name' to 'Budget Name Deleted')Now you should be able to create a new budget with the desired name in the UI.