https://www.dailysabah.com/business/finance/nigeria-shutting-down-all-cryptocurrency-accounts

Accounts involved in the transfer or exchange of cryptocurrencies are to be closed down by Nigerian financial institutions per the orders of the country’s central bank on Friday, which warned of sanctions if they did not comply.

Cryptocurrency can be P2P. This means you can transfer cryptocurrency from your mobile phone to some other person's mobile. People don't carry a lot of money around these days?

So technically, if I use my bank account to buy bitcoin from a friend (or anyone), then my account could be frozen.

Meanwhile

Tesla has acquired around $1.5 billion in Bitcoin under an investment policy at the electric car maker headed by Elon Musk, and it plans to begin accepting the digital currency as payment for vehicles soon.

The California company revealed the new strategy in a filing with the U.S. Securities and Exchange Commission early Monday, saying its investment in digital currency and other "alternative reserve assets" may grow.

Wedbush Securities analyst Dan Ives called Tesla's move to back the cryptocurrency "a potential game changing move for the use of bitcoin" to make retail purchases.

https://www.msn.com/en-us/autos/news/bitcoin-prices-soar-as-tesla-says-it-bought-2415-billion-worth/ar-BB1dvcvP

Why didn't USA ban Tesla?