I just responded to you in the other thread you posted in. Here is the response I posted, and after you have read it, either respond here or in the other thread. No need to respond in both...
We're still not sure what causes this to happen, as it only seems to be something that happens randomly only affecting a small handful of people. So far as I know, the only way to get the issue fixed is to reinstall mSecure on your iPhone. This will not only delete the app from your iPhone, but it will also delete it from your watch as well. After the re-installation on your iPhone, it will be installed the watch as well.
Before you do this, do you have access to your information in mSecure running on a device other than your iPhone? If not, do you have another device we could get mSecure installed on before you go through the re-installation?
This subject started over a year ago it seems. My Apple Watch 7 and mSecure iPhone version 5.7.3 (784) fails to work. Has mSecure plans to fix this issue without reinstalling mSecure?