Hi Grant,
Thank you for contacting us. I answered this in the other thread you posted in, but here is what I wrote...
I'm not sure what is causing this, but we should be able to get it to work without too much trouble. I'm going to have you turn off the Face ID feature in mSecure's Settings, then you reboot your phone, and then re-enable the Face ID unlock feature. You can follow the steps below:
Did that have any effect on the problem?
Grant