Portuguese to English Law/Patents Human Resources Section of a Labour Act

I am translating sections of the Labour Act of Guinea-Bissau from French, but the Fr was translated from the original Portuguese (which I do not speak), and this paragraph is so ambiguous, I have had to refer to the original (I have only a really faded scanned copy) - and it is still ambiguous. I am not sure if it means that public holidays have to be paid, but may not be paid as overtime (presumably not at time-and-a-half or double time, for example) OR if it means that the employer is not allowed to ask them to work extra overtime to make up for the lost hours; OR that they may not be cajoled into working on Public Holidays by being paid for them as overtime. The heading of the Article is "Feriados nacionais - Garantias da retribuição" (very faded section of the copy). Any input will be greatly appreciated.

"O trabalhador tem direito à retribuição correspondente aos feriados nacionais, sem que o empregador os possa compensar com trabalho extraordinário."