Please try is as below.This is just a sample.Adjust it according to your app.
Step 1 : Retrieve your db object which you want to update.
i.e.
var invoiceConfigobj = (from invoiceConfig in Catalog.InvoiceConfigurations
where invoiceConfig.Provider.Id == providerId
select invoiceConfig).SingleOrDefault();
Step 2 : After that update the fields which you want and save it back.
i.e.
invoiceConfigobj.IsAllowInvoice = allowInvoice;
invoiceConfigobj.IsCustomerInvoice = customerInvoice;
invoiceConfigobj.Schedule = scheduleType;
invoiceConfigobj.ScheduleDate = scheduleDate;
Catalog.SaveChanges();