iPhone 12 mini bought in United State not reading sim in United Kingdom

sometimes this year, I purchased an iPhone on amazon, iPhone 12mini, had it sent to Nigeria where I used it for about four months.

now I am in the United Kingdom but the phone is not reading any United Kingdom SIM card that I insert.

any help out here, please?

**I have done a hard reset in the phone.

The network provider lock is not restricted also..