Labour Law and Labour Protection

Inga is working in private enterprise. She gets a salary only once a month, but she knows that in some companies salaries are paid twice in a month. When Inga informed of their desire to receive salary twice a month, employer refused, based on the grounds that this is a private company and organization of payment procedure is right of employer.
Please, give analysis of this case, based on the provisions of the Labour Law of Latvia and Labour Law of any other country. If