Why can I receive texts from everyone else except this one?

The reason why you are not able to receive texts from some but can receive from others is likely because the texts are not sent as SMS messages.  Text messages can be sent in different forms.  The most common are SMS, MMS, RCS, and iMessage.  Tobii Dynavox currently only accepts SMS (with the exception of Beam which also accepts MMS).

You can ask the sender to send the message as SMS by asking them to change their settings.  The instructions below may help the sender make the change however iPhone and Android screens do tend to change over time so for the most accurate instructions you may need to check their websites.

iPhone

1. In Settings, choose Messages.
2. Turn on Send as SMS

• Make sure you message contains less than 160 characters
• Make sure that the sender is sending to less than ten contacts.
• Some Android apps have a Group messaging setting and will send MMS instead of SMS automatically unless changed in the settings of that app.
• Since there are many messaging apps for Android, there are no set steps to make sure the sender's messaging app is sending the text as SMS.