SMS failed when network is on wifi

[zoesyl333]

I don't understand why I have to turn mobile data on to send the SMS.

When I sent SMS over wifi, it always failed to deliver. I had to turn on my mobile data to resend it. 

[Original_Lucy · Accepted solution]

Hi there @zoesyl333 , to send sms you require a cellular connection.  If you have wifi calling you can send sms over wifi. So, yes you would need a cellular connection unless you have wifi calling.