SMSC is configuration issue

Hi

Earlier this evening all of sudden I couldn't send out any text. Then it worked again shortly after.

I have the latest ios update; I've restarted the iphone.

I used whatsapp to reach Fizz c/s. They keep on asking to do the following:

Verification on iPhone: Dial *#5005*7672# → Press the key to place the call. 

Editing on iPhone: Dial **5005*7672*+14385200092# → Press the key to place the call.

Source: https://fizz.ca/en/faq/i-cant-send-or-receive-text-messages

From this article https://www.techtarget.com/searchmobilecomputing/definition/short-message-service-center , it says (of course I don't know when this was written and which country)

SMSC in Apple iOS

To update the SMSC on an Apple iOS device, open the settings application when on Wi-Fi or connected to the carrier's cellular network. Navigate to General, then About. If an update is needed, users will see a prompt to update the carrier settings.

Previously iOS users could see their SMSC in a manner similar to Android using the following steps:

• Open the Phone
• Dial *#5005*7672# then tap Call.
• The current SMSC number will be shown.

This process now results in an error message.

Has anyone encountered this similar issue and if it's okay to leave it as now my text is working again.