Dear Lubos, possible in the future Find and merge option for customers and suppliers, because some time the user is mistakenly creating the same customer or suppliers
On a similar note, it would make sense for the application to warn the user if they are creating a Customer or Supplier that looks like it might be a duplicate. Doing so would prevent this scenario from occurring in the first place.
A similar name or email address would be a clear indicator that the new record being created is a potential duplicate.
Then prompting the user: “It looks like this Customer/Supplier already exists, would you like to continue?”