Why is the visa check in Nigeria so strict now?

This is mainly because there are many Nigerians in China and China, and there are cases of overstaying visas and non-work visas, and the situation of illegal residence is also very serious. This is based on the principle of diplomatic reciprocity. The Chinese side strictly manages the visa examination of Nigerians, and the Nigerian side also strictly examines the visas of China people. However, it is generally not a big problem to return to Nigeria after the visa expires, as long as you give some money to the immigration officials when you leave the customs.