IPhone 12 overseas SMS reminder is off.

The Japanese version of Apple may automatically send overseas text messages, or you may have turned on Imessage. Imessage will change automatically according to who you send messages to.

Two situations:

1. If Imessage is also turned on for this object, your short message will be sent out from the network channel. The nature is similar to WeChat.

2. If the object doesn't open imessage (or he's not an iphone), then your SMS will go out in the form of ordinary SMS, taking the channel of the telecom company. Your situation can be 1, but the network situation is not good and you can't send it out.