I have a Samsung S10 but I also had this problem with my s8. I used to send texts over the wifi in airplane mode with not issues as long as advanced calling was activated. However in the last 6 months, this only seems to work for the first few minutes after a restart.
I put the phone in airplane mode, turn on the wifi, verify the wifi is properly connected and then attempt to send the text. On my new S10, I automatically get a pending message that states it can't send in airplane mode. I select restart and restart the phone. After the phone comes back up, it shows that the text is sent and I have been told that the received did receive it.
This is a very annoying situation. As a results of this issue, I have to restart my phone many times a day especially if I am expecting a text. Is there a setting or system change that is causing this to not work. I was able to use this function, since advanced calling was first created, why doesn't it work now?
