If you earn in dollar, you do not really benefit from the US dollar price increase as naira is decline in price. Let me explain.

If you are collecting salary in Nigeria, your boss may take time before increasing your salary. This is a disadvantage. But later the salary would be increased.

If you are a seller or providing a service, as things are getting cost, you will increase the price of what you are selling or the service that you are providing and you will not lose if you are smart.

If you earn in dollar, the dollar price is increasing but the goods and services costs are increasing.

This is not possible. Probably you mistyped this figure.