company i work for is a corporation, they have many branches of stores, nvc wants a letter from the employer
can the manager write this letter?
Employment / Labor Attorney
I am not sure who "nvc" is, but the basic rule is that the company acts through it's officers and employees who the corporation has given the authority to act on it's behalf. So, if the company is Walmart and the act is the sale of product, Walmart has authorized it's cashiers to accept payment for product purchases.
The best way to find out if your company authorized your manager to write this particular letter is to ask the manager. He or she should know.