Do you talk directly to the person?
It can be daunting to communicate with someone who has difficulty understanding you or trouble getting their message across.
However, it is important to talk directly to the individual instead of the person with them. After all, they are the customers.
Smiling, saying hello or shaking hands (if appropriate) can put a person at ease and creates a more positive experience. Customers are more likely to return to a business that is welcoming and friendly.