I have had my S10e for about 3 weeks. I have a user that I received messages from and to on Jan 6, but now I don't receive any messages and when I try to send one the message dissapears and the app closes. I've tried it with wifi and wifi calling on and off and same result.
Are you only experiencing these symptoms with a specific user? Are you using the stock messaging app?
A week ago it happened with 1 user, but then after 3 tries it went away and the texts went through. Currently it is only happening with another user, however since I'm not receiving texts from that user either I don't know what texts I'm missing. That user does get my texts when they are in a group text. Yes, I am using the standard messaging app that came on the phone.
I would recommend reaching out to your carrier for further assistance.