Hi there and welcome
What exactly happens when you try to send a test message? What error do you receive?
Can you please hold the power button down until you see a menu and choose Power Off.
Then power it on and tell me if it then sends please.
ok, can you remove the battery please, wait 10 minutes, connect the battery and power it on and tell me if it then sends please.
Are you still able to receive messages?
And have you tried sending to multiple contacts?
ok, the message center address is critical, it is not your number, if this was changed it will be the issue
Who is your provider? AT&T?
Please set this as the number
Once saved, restart the phone and tell me if it now works please.
just to rule out an issue on your husbands phone, have someone else message you please
No, but you may have corrupted the phone trying to fix this as the service number was the issue.
We need to do a reset of the phone, this will remove all data and contacts and return the phone to new, but we cannot avoid this.
To do the reset.
Go to settings, Backup and Restore, Factory Reset
Perform a reset of the phone, once done, set it up and it should now work
Let me know the results please.