Well, as we know that the memory of your Android phone where all text messages are stored is always limited. If the capacity of the inbox of your Android phone reached a certain degree, you cannot receive new messages any more unless you delete some old ones. However, many messages are so important that you want to keep forever, so what will you do to solve this kind of problem? Then I suggest you to make a copy of text messages on your computer before deleting them from your phone. In fact, you may need to export SMS messages from Android phone to computer in many situations.
While, we all know that we are not able to transfer text messages or contacts from Android phone to PC unless we turn to a third-party program for help. Then you can choose Coolmuster Android Assistant to help, it's easy to use.
https://www.youtube.com/watch?v=oF--Y8I1qb0