Service number, mainly used for service. There are many interfaces to open the service number, such as payment, card voucher, customer service, message template, device function and so on.
Enterprise number, mainly used for OA office within the enterprise. Although the number of people is small, the news is not limited, which is convenient for internal communication. If we continue to develop, we can do things like punching cards and invoices.
I suggest you apply for a subscription number!