Why does the Apple phone repeat the same message twice? Should it be set in the phone, or is there something wrong with the phone?

How to solve the problem of repeated text message reminders on Apple mobile phones: It may be caused by turning on the "repeat reminder" function. In Settings - Notifications - Information, just turn off the "Repeat Reminder" function at the bottom. After turning it off, the new text message will only ring once to alert you, regardless of whether you have viewed the new text message. If this function is turned on, as long as you do not check this new text message, your phone will ring repeatedly to remind you to check the text message.