Nigeria cancels already issued visas for travelers from 13 countries

I couldn't find any recent information or credible sources indicating that Nigeria has cancelled already issued visas for travelers from 13 countries. It's possible that you may have come across outdated or incorrect information.

However, it's worth noting that Nigeria has been known to impose travel restrictions and visa requirements on certain countries or individuals in the past. For example, in 2020, Nigeria suspended the issuance of visas to travelers from 13 countries, including the United States, Canada, and the United Kingdom, due to concerns over the spread of COVID-19.

If you're planning to travel to Nigeria, I recommend checking with the Nigerian government's official website or contacting the Nigerian embassy or consulate in your country to confirm any travel requirements or restrictions that may be in place. You can also check with your airline or travel agent for any updates on travel restrictions or requirements.

It's always a good idea to stay informed and up-to-date on travel requirements and restrictions before planning a trip.