Thank you for contacting us, and I'm sorry for the issue you are experiencing. You shouldn't have any problems signing in to mSecure on your iPhone X. I just tested this on my iPhone to be sure there aren't any unknown issues with the Sign In process.
Please restart your iPhone and then open mSecure and try to sign in again. Did that have any effect on the problem?
I have successfully set up Msecure on my PC. I am trying to set it up on my Iphone X. When I try to Login, it just spins and doesn't bring me to the verification page or anything else.