This is due to buying the phone from Best Buy. Best Buy's new Apple phones (even if claimed to be "unlocked") are configured to automatically carrier lock to th

This is due to buying the phone from Best Buy. Best Buy's new Apple phones (even if claimed to be "unlocked") are configured to automatically carrier lock to the first SIM inserted. Fi's primary network is T-Mobile, so they lock to T-Mobile. See the many complaints in these search results: https://duckduckgo.com/?t=ffab&q=best+buy+lock+to+first+SIM&ia=web https://duckduckgo.com/?t=ffab&q=best+buy+lock+to+first+SIM&...