The location of our ancestors by any of the DNA testing firms is a matter of statics. How your DNA matches up to the information in the DNA testing firm’s DNA database gives you the results reported to you.
Nigeria is not a homogeneous country. If I recall correctly, Nigeria is made up of many different tribes and/or ethnic groups. If the 23andMe had a better sampling of the DNA from across the different groups in Nigeria, they could have reported what tribe your ancestors were from.
Some DNA testing companies have databases and algorithms that more accurately report one’s Jewish ancestry and location.
Family Tree DNA and MyHeritage are two DNA testing companies who I have found to more accurately report Jewish heritage. I am aware of other people who knew they were crypto Sephardic Jews and felt they did not get an accurate DNA report.
It is possible to transfer your 23andMe DNA data to the two companies referenced above. The DNA report from these other companies will likely show different results from what you already received.
Search the Internet for instructions on how to transfer DNA data between testing companies.
All the Best,