Android phones can't receive messages from iPhone

I purchased a new phone 7, and new number, for my daughter this Xmas. She recently told me two of her android friends weren't able to receive her texts. I looked into the imessage settings and this is where I am having difficulty finding info. The imessage option in settings is "on" but faded. I am unable to select or unselect it. Also, the face-time option is also "on" but unselectable. I logged into her appleid and havent found any setting prohibiting. Her age on their is an adult age so I wouldnt have to deal with certain things working and not working. I have parental controls on but haven't found any reason for it to block this. I also have an older daughter with which i have the same parental settings turned on and her imessage works fine. I have done search after search on-line and keep finding the same thing, "turn off imessage and it will work". I am unable to do that. I have also contacted Verizon and they have no clue either. HELP???

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