Same here. I also work with people around the country (from London to Scotland) who are experiencing the same issues. I'm unable to receive verification texts through my remote working authenticator, and even texts from a friend (who is on giffgaff/O2) aren't coming through.
Called support, they detected no issues with the towers, but reset my network profile and told me to manually search / reselect the network in my phone's settings and restart the device.
After doing so, I was able to send and receive ONE verification number from the remote access app, but none of the previous ones came through, nor did my friend's text. Now it's gone back to doing it.
Another thing which may or may not be relevant, in my iPhone X's mobile network settings where you can choose "automatic" or manually select the network in the list, if I select Virgin, after a few seconds or so, it deselects it again 😞
I had tried mine in another device and had the same issue. Fortunately whilst being on the phone to Customer Services trying all manner of resets, more reports of the same issue were coming in. This was then flagged as a network issue.
For me at least it was resolved late in the afternoon. I don't use sms much except for verification purposes and so far that has continued to work.
Fingers crossed others have had a similar resolution.