You must follow up customers and stand on the problems and find solutions in order to strengthen the relationship between sales and customer?

yes, it is true, we must stand at the problems of customers and find satisfactory solutions for customers in case there is any error or problem that occurred to them. Or give them options that satisfy them to solve their problem

Follow up the costumers is very important issue to knwo what we have missed

the main objective of the commercial operation is the satisfaction of the customer. and to do this, the product must meet the needs expressed by the customer (product quality, price, assurance, after-sales service, durability ...)

you must either solve the problem or should satisfy the cusomer with your answer. Satisfaction is the main key to relationship building.