Did u find a solution to this issue?
I'm currently having same issue with my new S10.
I've recently started having a problem with the chat mode on the default messaging app on samsung. Previously I was able to use chat mode just fine, with no problems. However now for the last few days, the chat mode will no longer send messages. It auto selects to use chat over SMS, and will act like the message is sent by giving me a date, but will not display a recieved or read notification, and the message never sends or auto switches to send it as SMS.
I've tried clearing the messaging app cache, cleared the phone cache, and even uninstalled new apps that have been downloaded since this issue started. I have not done a factory reset of the phone, and reluctant to resort to this. I have seen other threads from 6+months ago about a similar issue, but again the fixes they mentioned were clearing the cache and that has not worked for me.
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