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Hello I am trying to send a text to a number to opt in to receiving notifications about a program and it won't send the message. It keeps saying it failed. It is not just this number. I have tried to reply to drs offices automated texts to confirm appointments and it doesn't send. How do i fix th
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Hey, so my friend got a Galaxy s6 edge yesterday and gave me his new number. When I tried texting it I received this immediately after:Error Invalid Number. Please re-send using a valid 10 digit mobile number or valid short code. HeyI can receive messages from this number as well as calls. I've beco