Welcome new and old customers to inquire, right?

Yes, this sentence means welcome new and old customers to call the company for consultation. In which "incoming call" refers to telephone consultation and "inquiry" refers to inquiry or consultation. This sentence is usually used in company advertisements or websites to attract potential customers and show the company's professionalism and services. At the same time, this sentence also expresses the company's attention and enthusiasm for customer service, making customers feel professional and friendly.