When people call me, they can only hear text messages. What is the reason?

May be the reason of limited call barring.

When someone calls you, you will receive a message to remind you, depending on whether it happened to the same person. If there is only one number all the time, then you may have set this number as rejected. If there is another situation, such as no answer for a long time, then set call forwarding. You need to see the situation clearly.