You are afraid that the factory will see the contact information and rob your customers. Factories have to make orders, which they must know and cannot avoid.

You can sign an agreement with the factory in advance, and your customer factory can't contact directly, otherwise, ....

Customers must provide you with the best service. Trading companies still exist because there are many advantages that factories do not have.

The best way is to find a factory that doesn't do foreign orders directly, which means there are no direct foreign language personnel in the factory.